A bug affecting some players of Borderlands 2 is apparently wiping unlocked progress on all platforms. As noted in a 33-page thread on the official Gearbox forums, some players are starting up the game to find Badass Ranks, golden keys, heads, skins and achievement progress reset to zero. Worse still, menus displaying the content or challenges don’t actually reset, meaning the game thinks the content is unlocked even if you don’t have access to it, so you can’t re-earn skins or replay challenges in order to get them back.

The bug in question can be seen in the video below from YouTube user RyogaWanderer

Source - IGN

Well, got my first character to 50, now is a good time for me to take a break for other games. Just got a wired 360 controller to use for my PC and Tony Hawk Pro Skater HD so I'll just go with that in the mean time.

Just backed up my PC saves just in case, thanks for the heads up.

Playing Torchlight 2 at the moment anyways. I think I'll play that until Dat is caught up and done with the first playthrough, then join you all for playthrough 2.

Yep. Saves backup time.

Has this been fixed? I was just thinking of firing it up and completing the dlc. That being said, anyone up for some BL 2? It's a 2.5 playthrough at level fifty.

I'm not sure if it has or hasn't. Just know they were working on a fix for it.

I think they have, but you might want to read through the patch notes:

http://support.gearboxsoftware.com/entries/22147216-xbox-360-update-information