I'll believe it when I see it
The trouble with articles like this is that we rely heavily on Microsoft handouts for the substance, and they are willing to say anything that is likely to get the punters interested in buying. It's good that they have finally realised how much Vista is flawed, but they still haven't quite got it through their thick skulls that completely replacing an OS to satisfy the whims of the marketing department is doing them more harm than good.
Why does XP need to be completely replaced? If the only reason you have is "because it's old", then the marketing oiks have won and you may as well forget any good intentions you might have with W7. Vista is a dead end, a flawed release that should be left behind. Start again and produce something that is actually an improvement on XP rather than try to find excuses and cut chunks out of the flawed body. Don't just put out loads of buzzwords to try to placate the people having to make sense of the mess and, above all, don't make promises you can't keep.
After all, there's a reason why I still have a working RISC OS system under the desk beside my more up to date kit. It might be dated, and it might not do everything that a modern system can do, but it does what it can do well, without fuss and without the shedloads of bloated wizards and "helpful" crud that Microsoft feel I should have. When I want it to. Not several seconds down the line once the system decides I need to do it or when some process finishes analysing every nuance of my request. And it does it on a processor that is considerably less powerful than the systems in common use these days.
So go on, Microsoft. Bite the bullet. Admit Vista was a mistake and consider the alternatives, OS X included. Drop the bloat, the resource hogging crap and the DRM and put out something decent for once. It's only your profit margin that you need to consider.