Without knowing anything about the Microsoft tablet announced earlier this week, I can predict with a high level of confidence, based on my experience working for, with and against Microsoft, that it is going to fail. Microsoft sells its flagship products, all necessities, via OEMs (e.g. Dell and HP) and channel partners (large retailers and consultants) using a variety of sticks and carrots. Microsoft has never been able to sell directly to consumers and selling tablets is all about selling an experience to consumers directly. If they don't like the experience, no sticks nor carrots will change their minds. And that will not change for such a huge, byzantine company unless something really bad happens or after Bill and Steve move on.
P.S. I know Xbox is the exception. The video games console market is different from the technology market in many ways. Will try to cover that in another post.