PS3 disks can even hold more data cause of Blu-Ray. So that means their games can be bigger, better and longer.
-It doesn't cost much to have multiple disc so bigger and longer is not really true if it's needed they will just go multiple discs or download content.
-Just because PS3 discs can hold more data doesn't mean its games are "better"
-PS3 has some great specs in certain areas, but then they are bottlenecked in other areas. Besides the advantages of space on the disc (which is counter balanced by the SLOW disc reading speed) you aren't going to see much difference EVER between PS3 and 360 games. There is nothing on the PS3 as of yet that the 360 couldn't handle and I doubt there will ever be.
-In fact the best currently released game out there is Gears of War for 360 (not PS3)
-I and milions of others are still perfectly happy with DVD9 as standard media format for movies and games. Until HDTVs and such become really cheap I see it staying that way.