The awarding of the Nobel prize was not something Obama asked for or had any control over. It should not be held against him.
I personally don't recall Obama running on a platform of pacificism. From what I recall, his opinion on the current wars matches mine: the war in Afghanistan made some sense in the wake of 9/11, when it was clear that the Taliban government was supporting Al Qaeda. Where the Bush Administration erred was in launching a second war in Iraq two years later, which had little to no relation to 9/11. It was this second war that consumed most US resources for years, leaving Afghanistan forgotten. The early progress and support that was gained in Afghanistan has now been lost and will be difficult, if not impossible, to regain.
But the damage has been done. The war in Afghanistan is underway, and Obama can't change that. To abruptly pull out all troops and end the war would be tantamount to admitting failure. It would also cement all the billions of dollars and thousands of lives lost so far as a 100% waste. The mere perception that the US has been so utterly weakened would embolden terrorists and diminish US influence in the world. It would also reaffirm the general perception by most Republicans and some centrists that the Democrats are more cowardly than the Republicans. Should another terrorist attack occur during Obama's term the Democrats would then be doomed for another decade or so.
Obama's new plan, therefore, makes sense on paper. He's trying to end the war soon (2011 is around the corner) and is trying to rectify Bush's mistake of pulling troops and resources out of Afghanistan to send them to Iraq. He's trying to stabilize the country enough the US can pull out without utter disaster, and with enough positives to point to that the end result can't clearly be called a "failure" or a "lost war" -- even if it can't clearly be labeled a "victory" either. The war won't be 100% success, but it won't be a 100% of a waste, either. In a perfect world, the pullout would be well underway by 2012 when Obama's term as President ends, allowing him to declare that he has fulfilled his election promise of ending the war, while simultaneously not appearing to be weak when it comes to the defense of the US. It's a complete compromise, and a sensible one.
That of course, is on paper. The reality of Afghanistan is much messier and I'm apprehensive. I would be surprised if the plan doesn't go awry sooner rather than later. But right now I think Obama is between a rock and a hard place: he's stuck with the problems caused by the previous administration, and try as he might, I'm afraid he will be blamed for the resulting disasters. As much as I like Obama, I've had a bad feeling from day one that the winner of the 2008 election was doomed to failure due to many problems beyond the elect's control. This presidency could turn out to be the ultimate booby prize.
My biggest fear is that the result of Obama's presidency will be a hard swing to the right in 2012 as Americans react to the many, many problems that surface during Obama's presidency -- ironically forgetting that all these problems have their root causes in the 2002-2008 Bush period. Afghanistan is just one such example (the economy being another). Sometimes, there is no perfect solution.