Touch Arcade is that games are loading faster on iPhone 3GS compared to the plain, old 3G (see videos after the break). The revelation comes as little surprise considering the bump in processing power, but there may be a few surprises lurking for early adopters. Case in point: Check out Touch Arcade's comparison screen of Snowboard TnT above. It's like the game's graphics can't even keep up with the speed of the 3GS! Wow.
It's unlikely we'll see many leaps in existing games (perhaps some sharper 3D renders and improved frame rates here and there) and any glitches in the move to 3GS will hopefully be addressed with the quickness, but as soon as developers get to tinkering with the 3GS's superior technology there could be an entire class of games that are unplayable on a 3G or, dare we mention, the original iPhone. Of course, doing so would essentially cut off twenty-some-odd million potential app buyers.
Needless to say, we don't think it's realistic to expect a ton of support for 3GS-only gaming until the older iPhone models are phased out. In the meantime, you'll have to stick to bragging about those blazing load times.