Well, isn't that funny, I had a look this morning at the Sharp TVs on the BB website and there they are: new models, LC-60LE650 and LC-70LE650. Pauls TV has them too, but no one else yet that I could find.
Doesn't look like there's a manual available yet at sharpusa.com, and the features list doesn't have much information.
Comparing the features lists of the 640 and 650, not much difference.
-Surround Sound: Yes for the 640, Simulated for the 650. (Well of course it's simulated, both of them).
-Audio inputs (L/R): 2 on the 640, 4 on the 650.
-Slight differences in dimensions and weight. Probably not significant as those are often, hmm, less than precise. Just guessing, but a style change (thinner?) to the bezel could account for some of the difference in dimensions and weight.
-Everything else the same.
The thing that strikes me is the price at BB of $2,000.99. That's starting out significantly lower than the 640 did, IIRC.
I've been thinking about picking up a 640u while they're still available, but that 70" 650 is tempting. I'd like to see some reviews. Maybe it doesn't have the 24 fps pulldown judder of the 640 when interpolation is off.