Without discussing which console will be better I hope you are kidding.. Ik don't believe for 1 second that 2 systems with completely different Cpu designs and completely different Gpu designs will render exactly the same result on your TV screen. There has to be (and will be) differences.
look at it this way. Take one AMD PC with a Nvidia GPU, and one Intel PC with an ATI GPU. In the end both are just as capable as each other. the graphics on a game that runs on both platforms will look the same. The games that are exclusive to both platforms will look fantastic on both. One system doesn't have a visual advantage over the other since they are both capable of the same basic feature set. The visual difference is goign to come down to the quality of artists.
No, I'm not kidding. So what if one chip comes out after the next. this is just like the PC chips these days. They have reached a platuea with features required to fully support DX and OpenGL 2.0. New features for future versions of DX and OPENGL will come out at a much slower pace, and the high cards are now basically fighting it out with the same features. The difference is, one can render a certain feature (or collection of features) faster then the next.
Now swithching back to consoles, I've been saying this a LONG time before PS3 was released. The only difference graphically you're going to see is that one console can render a certain scene faster then the next (under certain circumstances) you're not going to get, console x looks much better then console Y because of these really cool hardware features. Both consoles are capable of similar things. Very similar things visually.
PS3 may be faster in certain areas, and xbox 360 may be faster in certain areas. They both can render the same scenes, with the same textures, pixel shaders, lighting parameters, etc. The only difference is that one will be faster at doing so.
Now the automatic assumption many people on the net made when seeing the PS3 specs, was that "Oh wow it's gonna look beter than xbox 360 since it's more powerful". In reality this isn't the case. The bad multi platform games will look bad on both systems. the good multi platform games will look good on both systems. Both systems will have games that look bloddy amazing and will be exclusive.
PS3 however won'have a button to push that makes graphics in games look better then xbox 360. That will come down to the quality/capabilities of the artists.
For me this will be interesting to find out.
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