diff --git a/AFNetworking/AFHTTPClient.m b/AFNetworking/AFHTTPClient.m
index 4e3bbd1..0e136cb 100644
--- a/AFNetworking/AFHTTPClient.m
+++ b/AFNetworking/AFHTTPClient.m
@@ -579,35 +579,42 @@ static void AFNetworkReachabilityReleaseCallback(const void *info) {
                               progressBlock:(void (^)(NSUInteger numberOfCompletedOperations, NSUInteger totalNumberOfOperations))progressBlock 
                             completionBlock:(void (^)(NSArray *operations))completionBlock
 {
+    __block dispatch_group_t dispatchGroup = dispatch_group_create();
+    dispatch_retain(dispatchGroup);
     NSBlockOperation *batchedOperation = [NSBlockOperation blockOperationWithBlock:^{
-        if (completionBlock) {
-            dispatch_async(dispatch_get_main_queue(), ^{
+        dispatch_group_notify(dispatchGroup, dispatch_get_main_queue(), ^{
+            if (completionBlock) {
                 completionBlock(operations);
-            });
-        }
+            }
+        });
+        dispatch_release(dispatchGroup);
     }];
-    
-    [self.operationQueue addOperation:batchedOperation];
-    
+
     NSPredicate *finishedOperationPredicate = [NSPredicate predicateWithFormat:@"isFinished == YES"];
     
     for (AFHTTPRequestOperation *operation in operations) {
         AFCompletionBlock originalCompletionBlock = [[operation.completionBlock copy] autorelease];
         operation.completionBlock = ^{
-            if (progressBlock) {
-                dispatch_async(dispatch_get_main_queue(), ^{
-                    progressBlock([[batchedOperation.dependencies filteredArrayUsingPredicate:finishedOperationPredicate] count], [batchedOperation.dependencies count]);
-                });
-            }
-            
-            if (originalCompletionBlock) {
-                originalCompletionBlock();
-            }
+            dispatch_queue_t queue = operation.successCallbackQueue ? operation.successCallbackQueue : dispatch_get_main_queue();
+            dispatch_group_async(dispatchGroup, queue, ^{
+                if (originalCompletionBlock) {
+                    originalCompletionBlock();
+                }
+                
+                if (progressBlock) {
+                    progressBlock([[operations filteredArrayUsingPredicate:finishedOperationPredicate] count], [operations count]);
+                }
+                
+                dispatch_group_leave(dispatchGroup);
+            });
         };
         
+        dispatch_group_enter(dispatchGroup);
         [batchedOperation addDependency:operation];
+        
         [self enqueueHTTPRequestOperation:operation];
     }
+    [self.operationQueue addOperation:batchedOperation];
 }
 
 #pragma mark -
@@ -757,7 +764,7 @@ static inline NSString * AFMultipartFormFinalBoundary() {
     }
     
     NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:fileURL];
-    [request setCachePolicy:NSURLCacheStorageNotAllowed];
+    [request setCachePolicy:NSURLRequestReloadIgnoringLocalCacheData];
     
     NSURLResponse *response = nil;
     NSData *data = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:error];
diff --git a/AFNetworking/AFHTTPRequestOperation.m b/AFNetworking/AFHTTPRequestOperation.m
index be53c61..483fbc9 100644
--- a/AFNetworking/AFHTTPRequestOperation.m
+++ b/AFNetworking/AFHTTPRequestOperation.m
@@ -119,7 +119,7 @@ static NSString * AFStringFromIndexSet(NSIndexSet *indexSet) {
         dispatch_release(_failureCallbackQueue); 
         _failureCallbackQueue = NULL;
     }
-    
+
     [super dealloc];
 }
 
@@ -177,6 +177,7 @@ static NSString * AFStringFromIndexSet(NSIndexSet *indexSet) {
     if (successCallbackQueue != _successCallbackQueue) {
         if (_successCallbackQueue) {
             dispatch_release(_successCallbackQueue);
+            _successCallbackQueue = NULL;
         }
      
         if (successCallbackQueue) {
@@ -190,6 +191,7 @@ static NSString * AFStringFromIndexSet(NSIndexSet *indexSet) {
     if (failureCallbackQueue != _failureCallbackQueue) {
         if (_failureCallbackQueue) {
             dispatch_release(_failureCallbackQueue);
+            _failureCallbackQueue = NULL;
         }
         
         if (failureCallbackQueue) {
diff --git a/AFNetworking/AFImageRequestOperation.m b/AFNetworking/AFImageRequestOperation.m
index 3365a20..3821046 100644
--- a/AFNetworking/AFImageRequestOperation.m
+++ b/AFNetworking/AFImageRequestOperation.m
@@ -79,12 +79,17 @@ static dispatch_queue_t image_request_operation_processing_queue() {
     [requestOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
         if (success) {
             UIImage *image = responseObject;
-            
             if (imageProcessingBlock) {
-                image = imageProcessingBlock(image);
+                dispatch_async(image_request_operation_processing_queue(), ^(void) {
+                    UIImage *processedImage = imageProcessingBlock(image);
+
+                    dispatch_async(dispatch_get_main_queue(), ^(void) {
+                        success(operation.request, operation.response, processedImage);
+                    });
+                });
+            } else {
+                success(operation.request, operation.response, image);
             }
-            
-            success(operation.request, operation.response, image);
         }
     } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
         if (failure) {
@@ -106,12 +111,17 @@ static dispatch_queue_t image_request_operation_processing_queue() {
     [requestOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
         if (success) {
             NSImage *image = responseObject;
-
             if (imageProcessingBlock) {
-                image = imageProcessingBlock(image);
+                dispatch_async(image_request_operation_processing_queue(), ^(void) {
+                    NSImage *processedImage = imageProcessingBlock(image);
+
+                    dispatch_async(dispatch_get_main_queue(), ^(void) {
+                        success(operation.request, operation.response, processedImage);
+                    });
+                });
+            } else {
+                success(operation.request, operation.response, image);
             }
-            
-            success(operation.request, operation.response, image);
         }
     } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
         if (failure) {
diff --git a/AFNetworking/AFJSONRequestOperation.m b/AFNetworking/AFJSONRequestOperation.m
index 451705e..9d40368 100644
--- a/AFNetworking/AFJSONRequestOperation.m
+++ b/AFNetworking/AFJSONRequestOperation.m
@@ -114,7 +114,7 @@ static dispatch_queue_t json_request_operation_processing_queue() {
                 });
             }
         } else {
-            dispatch_async(json_request_operation_processing_queue(), ^(void) {
+            dispatch_async(json_request_operation_processing_queue(), ^{
                 id JSON = self.responseJSON;
                 
                 if (self.JSONError) {
diff --git a/AFNetworking/AFURLConnectionOperation.m b/AFNetworking/AFURLConnectionOperation.m
index 2b60952..2f1f5b3 100644
--- a/AFNetworking/AFURLConnectionOperation.m
+++ b/AFNetworking/AFURLConnectionOperation.m
@@ -130,18 +130,9 @@ static inline BOOL AFStateTransitionIsValid(AFOperationState fromState, AFOperat
 
 + (void)networkRequestThreadEntryPoint:(id)__unused object {
     do {
-        NSAutoreleasePool *exceptionPool = [[NSAutoreleasePool alloc] init];
-        NSException *caughtException = nil;
-        @try {
-            NSAutoreleasePool *runLoopPool = [[NSAutoreleasePool alloc] init];
-            [[NSRunLoop currentRunLoop] run];
-            [runLoopPool drain];
-        }
-        @catch(NSException *e) { caughtException = e; }
-        if(caughtException) { 
-            NSLog(NSLocalizedString(@"Unhandled exception on %@ networking thread: %@, userInfo: %@", nil), NSStringFromClass([self class]), caughtException, [caughtException userInfo]); 
-        }
-        [exceptionPool drain];
+        NSAutoreleasePool *runLoopPool = [[NSAutoreleasePool alloc] init];
+        [[NSRunLoop currentRunLoop] run];
+        [runLoopPool drain];
     } while (YES);
 }
 
diff --git a/AFNetworking/UIImageView+AFNetworking.m b/AFNetworking/UIImageView+AFNetworking.m
index 5310e71..ac1f708 100644
--- a/AFNetworking/UIImageView+AFNetworking.m
+++ b/AFNetworking/UIImageView+AFNetworking.m
@@ -115,6 +115,7 @@ static char kAFImageRequestOperationObjectKey;
         [requestOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
             if ([[urlRequest URL] isEqual:[[self.af_imageRequestOperation request] URL]]) {
                 self.image = responseObject;
+                self.af_imageRequestOperation = nil;
             }
 
             if (success) {
@@ -123,13 +124,16 @@ static char kAFImageRequestOperationObjectKey;
 
             [[[self class] af_sharedImageCache] cacheImage:responseObject forRequest:urlRequest];
             
-            self.af_imageRequestOperation = nil;
+
         } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
+            if ([[urlRequest URL] isEqual:[[self.af_imageRequestOperation request] URL]]) {
+                self.af_imageRequestOperation = nil;
+            }
+
             if (failure) {
                 failure(operation.request, operation.response, error);
             }
             
-            self.af_imageRequestOperation = nil;
         }];
         
         self.af_imageRequestOperation = requestOperation;
@@ -168,7 +172,9 @@ static inline NSString * AFImageCacheKeyFromURLRequest(NSURLRequest *request) {
 - (void)cacheImage:(UIImage *)image
         forRequest:(NSURLRequest *)request
 {
-    [self setObject:image forKey:AFImageCacheKeyFromURLRequest(request)];
+    if (image && request) {
+        [self setObject:image forKey:AFImageCacheKeyFromURLRequest(request)];
+    }
 }
 
 @end