The election results are in, and the Democrats are going to be in charge of the House. Final results in the Senate aren't in yet, but it's clear that the Democrats will have a stronger, if not dominant, voice in the Senate as well.
What's not yet clear is the impact of the elections on the estate tax. At least for now, I think it's safe to say that repeal is off the table. That would require Democrats to make repeal their issue, and that's just not realistic.
If I had to guess right now, I would think that we will see Democrats put forward a bill in 2008 to freeze the exemption amount at $3.5 million to prevent the "temporary repeal" in 2010. That would be a politically-expedient solution that could garner enough votes to pass. The Democrats' constituency would be happy that the temporary repeal would be prevented, and the Republicans would be able to avoid the unpleasant reversion to the pre-2001 $1 million exemption.
Another variant on this approach would see a freeze of the exemption at $2 million. However, that would involve putting the estate tax on the agenda for the first session of the new Congress. That would be a political risk for the Democrats, and I don't think it would be likely. (Although, it would be more likely if the Democrats could get a Republican quid pro quo in return.)
Further, I think that some sort of inflation index is more likely with Democrats in charge, because it will take the issue out of play in future years if Republicans regain control of the Congress. And, finally, I think "portability" is likely regardless of which party controls. Portability would permit a surviving spouse to use a deceased spouse's estate exemption without the use of a bypass trust. This change would have more impact on estate planning law and techniques than any change in the exemption amount.