Backwards compatbility won't be coming back, Sony made a delibate business decision to get rid of it. Basically, people were buying a PS3 and using it primarily to buy old PS2 games and neglecting cross-platform PS3 games ("neglect" being relative to whatever benchmarks Sony set for themselves); low PS3 software sales mean less third-party exclusives and support in general. It's the same reason they're phasing out Linux support - people spend too much time dicking around on emulators and not enough time giving Sony their money
It's a lose/lose for all involved and I can understand the problem but it wouldn't be an issue if the PS3 had more exclusive content. To be fair, all the PS3-exclusive .... I own is great fun - Valkyria Chronicles, the Yakuza games, LittleBigPlanet, Killzone 2 - but there just isn't enough of it to justify the price difference over the X360, especially if you couldn't give a .... about blu-ray.