What i wonder is, what kind of crazy developer would take 192MB for coding/level, would have to be very inneficient or just plain bloated, as if someone would say, to hell with streaming.
I think 360's unified memory is an advantage in the long run, the more devs will optimize the memory required for levels by streaming it, the more memory they could have for textures, while PS3, you're maxed at 256MB no matter what.
Anyway, the 2 will look very much the same, game graphics will mostly matter with how much time and money the developer invested into it, not the actual tech, devs like Square enix will make near CGI in real-time with all their experience over the years and enormous budgets, while smaller devs will scrape resources to just try and match the competition as best as they can and or afford.