The biggest hurdle that the PS3 will have to overcome.

[MikeB]

@ NJ5

And how long do you think it will be before such a game exists, considering the low sales of the PS3 so far?

To use the PS3 fully to its potential will take many years as the platform has a lot of headroom for developers to tap into. Motorstorm and Resistance are two examples which currently already use the SPEs. I know Resistance doesn't offer on par graphics with Gears of War yet, but according to Insomniac games that's mainly because the engine did not yet support texture streaming, which will be included in their later games. Personally I completed both Gears of War and Resistance and I honestly think Resistance is the better game and there are parts in Resistance later on with so many things going on at once it's really impressive without dropping frames and unlike Gears of War bodies stay around making the game look like a graveyard, windows partially break very realistically, soldiers follow your movements with their eyes, bodies can be pushed off ledges in a realistic way showing off good physics, etc, so overall I don't think Resistance is technically less impressive than Gears of War. Sadly screenshots don't show off Resistance and Motorstorm to the quality they are really offering, but the graphics are very good and their online component is very strong as well.

There are quite a few large budget PS3 exclusives under development.

how much money do you think would be spent in graphical content to fill up a whole Blu-Ray disc?

Often concept art already is of very high quality, later downgraded to fit the game. On the PS3 there is less reason to make compromises if the engine allows for good performance in combination with higher quality textures.