Tax mushiness

At some point, the Senate will decide to:
a) extend all the Bush tax cuts
b) extend some of the Bush tax cuts
c) temporarily extend all the Bush tax cuts
d) temporarily extend some of the Bush tax cuts
e) do nothing and let all the Bush tax cuts expire

To me, though, a = c and b = d.  See, we have elections for Congress every two years, and this year being divisible by 2, it means we have them this year.  And whatever Congress does now can be undone by Congress later.  And the people in Congress now are likely to be different from the people in Congress later, with a lot more having an R next to their name in the future. 

So if you are Democrats in charge right now, or, god forbid, the head of the party because you happen to be President, you might want to stake out some definable position that plans for Republicans being in the majority come 2011.  To be more clear, if Obama thinks that extending all the Bush tax cuts indefinitely is a bad idea, but won't veto it if it is only a "temporary" idea, then he's trying to fool himself or us or both.  Because if he won't veto it now, why would he veto it in a year when extension passes the Senate again?  If extending them is bad for the deficit now, why not later?