Nice catch. It'll be fixed next reboot.
17.Mar.2012 19:50:22 debug low - - Completing roll on item 1209 (Angel Wing):
17.Mar.2012 19:50:22 debug low - - Blizzardfoot (user-id 2918) rolls 10 (needs)
17.Mar.2012 19:50:22 debug low - - Assigning item to Blizzardfoot.
The roll was won by Blizzardfoot (she checked the "needs" box, thus everyone else who did not was bypassed), however when she couldn't pick it up, the item was "placed back" on the map. Since there's a timer that prevents other players than the roll-winner from looting the item, that's perfectly fine.
In case whoever rolled for the item doesn't claim it (they may have disconnected or such), the item eventually becomes free for all. Usually this only happens 10-20 seconds before the item expires, so there's plenty of time. However, for world bosses, the timer was much shorter, since the entire fight is supposed to be competitive between any groups that find the world boss at the same time.
After the update, the server will no longer imply that you won the item, even if you can pick it up because the loot protection timer expired.
In addition, if the roll winner cannot pick up the item, the loot protection timer is automatically extended by 30 seconds before anyone else can pick it up. This should be enough time to free up some bag-space.