Just upgraded to WordPress 3.3 and we can no longer upload images (old uploader just returns to the same page, or gives an "Are you sure you want to do that?" error, new uploader freezes at 1/3 on "Crunching" progress). We can't insert previously uploaded pictures either, if we select and image and click, it just goes right back to the selector.
Also, if a comment is held for moderation, and we try to delete or spam it, it just comes right back to the moderation queue.
Finally, popups like the ones introducing the new menu and new uploader pop up over, and over, and over, and over again. Every time.
Running WP 3.3 on Nginx with a CDN and WP3 cache.
Any help appreciated. We've already tried everything in the master list and other threads and none of it has worked.