One of the things that motivated me to take the jump to Micro Four Thirds was hearing the rumors from fairly plausable sources that Nikon was making a mirrorless camera with a sensor smaller than the 4/3rds sensor.... because I think that the 4/3rds sensor is about as small as you really want to go.
So it's interesting, in that it will probably cause the other players to improve, but I think Nikon is working too hard to make a SLR that deliberately doesn't compete with their dSLR lineup. It kinda reminds me of the Nikon Pronea SLR series, actually.
I don't think it requires supernatural powers to predict that many of you will be buying a mirrorless camera in the not-too-distant-future. After all, quite a few of you purchased G-series Canons after I got my G7 and your G-series Canon will eventually wear out.
There's still room for differentiation in the compact camera marketplace. The Fuji X100 has been selling quite well. The X10 should also sell quite well.