OMG, my brother just showed me a bug inside BBS. It was really funny... Spoiler He was playing with Aqua and suddenly Vanitas/Ven was floating upside down behind him. It lasted for about 5 minutes...
Intresting xD. Though I haven't expirenced many bugs/glitches in the game, but I have seen textures that look oddly sometimes. :/
Videos of similar glitches have happened. Like Vanitas Sentiment floating in the air and having the camera screw up. @-@ I dunno why I never had any funny glitches while playing through the game. I can't remember any glitch at all. ><
I found one where if you use Sleep on Vanitas while he's in the air from the endy part of that divey attack that he does, he'll fall asleep and be standing in the air. xD And another one where I was using a brightness plugin for my PSP that caused textures to turn white, making for a pretty damn awesome Aqua.