See, that's the "no fair!" comment I was talking about. You sound like it bothers you that they spent all this money.
As I said, if you spend a ton of money on marketing and people buy it solely because of that, you'll get good initial sales, but word of mouth/reviews will indicate future sales very quickly (as in a matter of weeks). That isn't the case with Kinect. It got a good wave of initial sales, and it *continues* to sell well not just because of marketing, but also because word of mouth is increasing its presence.
We already know it doesn't suck, but even if it did, we'd be hearing by now all kinds of anecdotes about lots of returns, stock piling up on shelves, bad reviews, negative press, etc... That's not happening.
So, good product + major marketing = major success.