Greg Sargent, who's been all over this story, has the scoop:

Steny Hoyer, the number two in the House Dem leadership, told Democrats at a caucus meeting this morning that they would get to vote this year on just extending the Bush tax cuts for the middle class, a senior Dem aide tells me, signaling support for a confrontational move towards the GOP that liberals have been pushing.
Asked if Democrats would definitely get a chance to hold this vote, the senior aide responded: "Definitely."
Hoyer's declaration comes as Democrats have been debating the way forward on the Bush tax cuts, and another aide tells me that "more than half" of the Dem caucus supports this course of action.

I say that if they want a separate vote on tax cuts for income over $250,000, they can have one.