What I expect (at the federal level):
(Green = could go either way, gray = will remain stable)
IMO, Mississippi and Alabama will shift democrat and california will remain stable.
My reasoning on MS and AL is that those two states, along with SC, have very strong racial polarization (with whites voting R in the high 70s, and blacks voting D in the 90s), which has maintained a fairly high degree of stability and even strengthened in recent years. I think that the coastal South (VA, NC, SC, GA) is going to become wealthier and gentrify quite a bit in the coming decades, which has a good potential to break down that racial voting pattern among whites in SC, but I don't see that sort of demographic/economic change happening as much in MS and AL, so I think they'll remain fairly stable for the time being. CA I was somewhat unsure of; my reasoning there is that I can't see it becoming any more Democratic than it already is, and if the budget and economic problems aren't solved there in the next few years, I think it'll be very damaging to the CA Democrats.
Of course, all of this is assuming no platform changes in either of the two parties, which isn't terribly likely; I think the Dems will shift more in a "Jim Webb" direction (to try to regain the white working-class voters they're currently shedding) and the GOP in a "Mitch Daniels" direction (to appeal more to wealthy, socially liberal, or minority voters). That would, of course, lead to a rather different map:
