From the New York Times:

“I am not inclined to support the Senate version,” said Representative Shelley Berkley, Democrat of Nevada, who voted for the House bill in November. “I would like something more concrete than a promise. The Senate cannot promise its way out of a brown paper bag.”

As far as I can tell, Berkley hasn't been on anyone's list as a House member likely to switch her vote from yes to no on health care. She raises a crucial point--that the Senate doesn't have to follow through on reconciliation changes once the House passes the Senate bill. As Jeffrey H. Anderson wrote yesterday:

Senators want nothing to do with “reconciliation” — whether politically or for what it would do to their chamber — and they already like their own bill (which the House would then already have passed) just fine.  The President would then already have gotten a bill through both chambers, and while House members would complain powerlessly, he would dip his pen in the ink and visualize himself in the history books.  He might even try to score a few extra political points by saying, As you know, we intended to use the reconciliation process to make a few small changes to the Senate bill.  While I know that there was some disagreement from some people, I think that that process would have been entirely appropriate to pursue.  But some people are uncomfortable with it, and I think that’s a legitimate concern.  It’s important to remember that our democratic institutions deserve the benefit of the doubt.  Also, the American people understandably think that we’ve been focused on health care long enough.  So that’s why I am making the decision not to pursue “reconciliation.”  Instead, I am moving on to a jobs bill….

House members would be left holding the bag.  Target squarely on their chests, they would now get to face their fuming constituents after having passed a $2.5 trillion bill that would allow public funding of abortion, would send $100 million to Nebraska, $300 million to Louisiana, $100 million to Connecticut, would exempt South Florida's Medicare Advantage enrollees from annual $2,100 cuts in Medicare Advantage benefits, would raise taxes, raise deficits, raise health costs, empower Washington, reduce liberty, politicize medicine, and jeopardize the quality of health care.  Most of all, they would feel the citizenry's wrath for having voted to pass a bill that only 25 percent of Americans support.

Democratic congressman Bart Stupak also says House members don't trust the Senate:

“You’re going to make members vote for a bill that’s going to be hung around your neck come Election Day,” he said. “After sending so much legislation to the Senate, we just don’t trust that they’re going to do it.”

Republican senator Judd Gregg raised the same issue this morning:

"They're using reconciliation to pass the great big bill," Gregg said during an appearance on CNBC. "Once they pass the great big bill, I wouldn't be surprised if the White House didn't care if reconciliation passed. I mean, why would they?"