Well, surely with next gen games instead of just a flat bitmap for textures, you'll have to multiple that alot for next gen gaming.
I do a bit of (crap) 3D work and for a good model you need:
Diffuse Map = Actual colour texture of your model
Normal Map = A 3D contour map so to speak
Bump Map = A fine detail map, grain or textile etc
Opacity Map = Maybe something is transparent
Glossiness = Does something reflect more than something else
Reflection
Self Illumination
etc etc
So the texture demands have more than tripled over last gen, and they can be nearly as big as diffuse maps.
And before people say, oh the PC has done that for ages, yes it has, thats why games are around or over 3GB HDD installs and remember to get the highest setting textures on Doom III you need a 512MB 3D card
As for Blu Ray, its a good thing, it pushes the boat out a bit further, sure if PS3 was DVD9, devs would find a way, but they don't have to. If they want to put extra content over a 360 version, they can and I like that!!
EDIT: Cliffy hows the PS3 build of UT2007 coming along? Is it running well?