Today is Day 2 of the 2008 Presidential campaign--they don't want to jeopardize their chances of recapturing the White House.
If they are talking about it, it means that they are planning it.
They are going to start with 'hearings' first.
They will deny that the purpose of these 'hearings' is to impeach Bush - but that is exactly what they will be doing.
They will probably work on the Vice president first.