Liberals are angry with Kent Conrad for saying that there are not enough votes in the Senate for a public option -- since, as Jonathan Zasloff argues, a key missing vote is Conrad's own vote. Is Conrad guilty of lying?
No, I don't think so.
What Conrad is saying is that he can't be the 60th vote; he (and a handful of others) need more political cover. A Democrats-only bill is going to be controversial, and Conrad is just saying that he isn't willing to cast that vote. Given that Conrad needs to get reelected in a state that McCain won by eight points, even though IIRC Obama ran a one-sided campaign there, I don't think that he's totally nuts to want to avoid ads saying that he was the one who put the bill over the top.
More generally...look, politicians are going to use politician language. Liberals would not be any better off if Kent Conrad went on the Sunday talk shows and said that he doesn't really care about the details of health care, but that he needs to get reelected, and so he'll vote for anything that has half a dozen Republican votes and against anything that doesn't.
The trick for proponents of reform is to find ways to make the vote non-controversial. One method is to figure out a way to entice a few Republicans to support it; another is to manage to convince people that the Republicans are so unreasonable that their "no" votes are out of the mainstream, thereby making yes votes less controversial. I do think the Obama team is making some progress with the latter approach, but this is hard going.