Battle for Bikini Bottom Version Differences

PS2: Slowest version, period.
GCN: Loads a little faster than the PS2 version.
Wii: Loads at the same, exact speed as GCN version no matter what model you use.
Xbox: Loads a little faster than the GCN version.
Xbox 360: Loads at about the same speed as the Xbox version.

*There are other, minor differences between the different versions, but none of them affect the game speedrun-wise.
**I'm not claiming to know absolutely everything about this game, which is why this information is based on the general consensus of this game's speedrunning community.
***I'll be getting the Xbox 360 version of this game soon, so I'm gonna sound like a hypocrite here, but please don't be discouraged from running this game simply because you don't have the fastest version. The overall timeloss that comes from version differences is probably close to a minute or so, so just have fun with your runs and don't focus on getting world record.