That's one prominent senator from either side of the aisle suggesting that the timeline should be flexible, an opinion that in Feinstein's case, at least, seems to be predicated almost entirely on the fact that Petraeus is running the show now.
Meanwhile, with Petraeus' confirmation hearing set to be held this week, [Sen. Lindsey] Graham said he wants the administration to clarify how hard-and-fast the withdrawal deadline is.
[Sen. Dianne] Feinstein said that if Petraeus asks for more time, "I would say give it to him."
So if the president decides he wants to "finesse the 2011 deadline," he's got Petraeus' cred on the Hill to work with. If he decides he doesn't, then he's got Petraeus (and Gates, and Mullen) on the record in Johnathan Alter's book saying that he's not going to come back later and ask for more troops, that he's not going to try to flex the deadline, that he thinks significant progress can be made in 18 (now 12) months.
Politics is about options, and now the president's got all he wants.