If the truth was known, I think Sony sees the 40 gig model as a cheaper blu-ray player first and a games console later in the future. They hope to sell a LOT of them worldwide even if the majority of them are buying it for blu-ray... Success means they make progress in beating out HD-DVD and will get royalty rewards in the future on blu-ray. The other battlefront, in gaming, is on the 60 gig since (at least in Europe) it is a better deal (+2 games +1 controller +BC). I think Sony fully knew well that the lower price console would help the more expensive console... It's "just" a little more and you get so much more...
I dont' know why everyone assumes BC isn't important to those that already have a PS2. I have a PS2 and BC is extremely important to me and I wouldn't own a PS3 without BC until the library is quite large.
I hate trolls.
Systems I currently own: 360, PS3, Wii, DS Lite (2)
Systems I've owned: PS2, PS1, Dreamcast, Saturn, 3DO, Genesis, Gamecube, N64, SNES, NES, GBA, GB, C64, Amiga, Atari 2600 and 5200, Sega Game Gear, Vectrex, Intellivision, Pong. Yes, Pong.