The way I see it, if there is a major revision to MBP, Apple would rather do it later than tomorrow. MBP needs updating on multiple fronts, processor, multitouch, keypad, video chip set, bigger HDD, etc etc.. and if these are to be done for the next update, they would rather call a press meet and update MBP along with the release of iPhone/iPod Touch SDK, instead of a calm web/store update.
MB and iMac on the other hand would get minor upgrades (AL MB(?), bigger RAM/HDD for iMac), which could possibly be done as part of these ongoing tuesday updates.
I agree with itsmeok. MacBook Pro now needs major work and they don't want to fluff it.
People have stopped buying them unless they really have to.
It will take more time to sort out as they don't want to go off half cocked now or they will lose serious face. Apple will come through with something great, it's what they do, but it probably won't be tomorrow.