I think MS isn't "fighting back" so to speak because they don't want to play forum-esque flame games
You're forgetting MS is applying the a similar battle plan they did when they took over internet browsers it didn't happen over night but you Remember NETSCAPE NAVIGATOR?
Before MS started their attack it was number 1 but now it's not even a distant 3rd
They know what they're doing... those who think MS isn't fighting back need to look at the whole situation from the BIG perspective. Right now you're down in the dirt with a microscope analyzing and nit picking moves. you need to get up in the sky and try to envision MS's plan as a whole if you want to truly understand what they're doing...
If you're able to see things from that perspective you'll realize that MS picks their battles and picks them well.
Think of it this way... MS had a very specific and deliberate marketing agenda... I'm sure most of us could quote their "mission statement" and all that HD era malarkey verbatim at this point... it's very obvious that MS has a plan... What's Sony's plan? we all watched their presentations, we've read their interviews, they've very obviously all over the friggin place. Their marketing strategy so far seems to be sitting on top of their hill and yelling "we're better than you" at the top of their lungs.