The only reason Apple has done so well the last few years is because Microsoft has simply ignored them. If MS were to launch an agressive advertising campaign that bashes them they way they’ve bashed Windows they’re screwed.
I mean Apple routinely lied in their commercials about how bad Vista was and people believed it. I haven’t seen a bash commercial in a while now, mainly because Windows7 is pure win. Now that they can easily win, it’s the perfect time for MS to start an all-out brawl.