Alaska, Oregon, Minnesota, and Georgia all have to go Dem to get to 60. Best case scenario for Dems is 59 seats and then Georgia going to a runoff, which they'd likely lose. So no, 60 won't happen, but maybe in 2010, and it's not that critical anyways. I doubt Specter, Snowe, or Collins will be voting to uphold many filibusters.
59 seats is the Democrat's ceiling. The Dems are at 56 right now. I'll give Alaska and Minnesota to Harry Reid, but I'm going to give Georgia and Oregon back to the Republicans, making it a 58-42 Senate. Plus, if the Democrats kick Joe Lieberman out of the caucus before the new Congress is sworn in and he defects to the Republicans, then it will be a 57-43 Senate. In theory, then, the Democrats would need 61 seats to be assured of a filibuster-proof Senate, and they're not going to get that.
I kinda think the Republicans are in for a better year in 2010. Of course, we'll have to see what President Obama does, but the Republicans should pick up a few seats in both Chambers. I don't see them retaking either Chamber in 2010, but they should pick up more seats, simply because the Democrats have more seats to defend, and things cannot get much worse than they are now for the Republicans. Remember, a lot of us thought the Democratic party was dead after their huge 2002 and 2004 losses, now look. The GOP will come back and they will come back very strong.