Probably not unless they face a serious challenge in their respective primaries. I'm not sure when they're do fro reelection, but I don't believe either has to stand for reelection in 2010.
They'll continue to have more "power" as deal makers or breakers, even if the Dems have 60. With Ben Nelson and a couple other more moderate Dems in the Senate, I don't believe a filibuster-proof majority will hold for every issue. JMHO.
Over the longer run, now the Democrats hardly need even inform the Republicans of their intentions or confer with them. No "earmarks" for Republicans and no spending in Republican districts. Too many voters will quickly vote for the guys that give them things.
Every concern I had during the general election has or will come to pass. This same sort of situation occurred recently in Southeast Asian (Thai) politics and the only recourse was a military coup which uncharacteristically handed power back to civilians.
Here, it may take an international terrorist confrontation to sway the public away from a one party dictatorship.