The PS3 games are all Blu-Ray. Although it may not seem like there are massive maps, long campaigns, etc., most of the storage goes towards graphics shading and rendering, which is the whole point of HD and Blu-Ray. After all, you could have a never ending game of pong, but how good would it look? As for the 360 having HD-DVD games, I think it's only a matter of tim.e
Now that the PS3 is out with its Blu-Ray player, and the Xbox 360 has its HD add-on, how long will it be before the gaming companies first release a next-gen game? With the next-gen format holding 20-60 Gb, the thoughts of a nearly limitless map on Elder Scrolls and Gears of War, and hundreds and hundreds of missions on Ghost Recon makes this gamer salivate!

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