My gut reaction is that this thing will simultaneously underdeliver on what it promises, and missed the point to begin with. However, I think Nintendo themselves missed the point with Wii Motion Plus.
What will be interesting to me is if they pull this thing off in the way they idealize. Meaning, will people embrace this style of control?
I'm not too sure. I think when the Wii was brand new and lighting the charts on fire, there was some sentiment out there that amounted to "The Wiimote is great, but I wish it allowed for even more realistic movement." However, as time wore on, it seems to me that the gesture based movement actually proves to be more conducive for easy, fun gameplay than the original dreams of 1:1 movement. For instance, Wii Golf. Originally, when it was shiny and new, my reaction was "This is great, but I wish it really matched my swing!" Over time, though, it became clear to me that I didn't necessarily want it to replicate my real swing, as I have a terrible slice in real life. For that matter, I really didn't want to stand up and pantomime a real golf swing -- especially without a real club in my hand -- for any significant period of time.
Of course, I may just be an old fart who resents change. Who knows. I'm the kind of person who played Punch-Out!! with the motion controls for all of one round before quickly conceding that I much preferred the old-school method. So what do I know?