Until reading this I had rather mixed feelings about the necessity for a timetable for leaving Iraq. What I do think is important - and it's time for the press to start asking - is just how permanent our designs on Iraq are? Why are we building the Biggest Baddest Embassy Ever and a bunch of permanent military bases? The elephant in the living room is of course the high probability that even if things work out wonderfully, and the security situation improves, the Bushies still intend to maintain a significant permanent presence in Iraq. Is that true? I don't know. But it's time for somebody to start asking.
Still, as upyernoz points out, if you lack a timetable (one filled with caveats and conditions and whatnot is fine) then it's difficult to ever credibly withdraw without granting the insurgents (or Michael Moore of course) the "credit."