The Xbox 360 has been out longer, but it's game library is still pitifully small. It's cheaper than the PS3, though not by any terribly significant margin when you consider they're both several hundred dollars.
I think most of the big name publishers have been holding off making new games until the PS3 and Wii were released. Now that they have, and are also now on sale in most of Europe, you'll probably start to see more games coming out.
Once they do, the PS3 and 360 games will likely look nearly identical if you're using HDMI or component cables. Most sports games will be put out by big name companies like Electronic Arts, who will make them for both the PS3 and 360. In order to reduce development costs, they'll try and keep things as similar as possible on each platform.
If you already have a lot of games for the Xbox I'd get the 360, and if you have a lot of PS2 games, I'd get a PS3, just for the backwards compatibility. If you have a lot of both, or neither, then flip a coin or something because the two are basically the same as far as you're concerned. I will say that the more expensive PS3 model has built in wifi, but the Premium and Elite 360 packages will come with wireless controllers. Maybe that will help tip the scales for you.
I have a 42 in 1080p Sharp Aqous TV. I have an extra HDMI. I would prob not buy any blu ray DVD's at this point. looking for the better looking, reliable, better games. Play alot of sports games.

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