I found a bug in which, when I hit "shift + delete" to permanently delete an item, the Recycle Bin's confirmation dialog popped up instead of the delete confirmation. Obviously, this would have been a big deal if I had hit shift by accident and didn't realize it. I couldn't reproduce it, though. All I know is that I deleted a about 1500 files, of multiple types, probably totaling 2GB in size.

Right, scratch that, I just did reproduce it. If you "roll" shift and delete, so that shift isn't depressed by the time the confirmation dialog appears, you'll be presented with the wrong dialog. It's probably related to the fact that so many files are being deleted at once, causing a split-second delay before the confirmation pops up (which is enough time to lift up shift).