Actually, its hard to really peg it for absolute certain as to what the future of the Corvette is with the Camaro due to be out soon, but my guess is that things won't change much in the near-future. The Camaro has had a long history of being not too far off the pace of the Corvette in performance, but enough to justify the price of the Corvette over all.
Given that the Camaro is based on the Zeta platform, and we do know that the G8 is certainly not a light car, my guess is that even in top trim (at least for now), we're at best going to see a 400 BHP Camaro. In that form, we could probably expect a high four second 0-60 run with a top-speed in the 160-170 range. Handling should be good for a car its size, probably just a hair or two better than where the GTO/Monaro CV8 left off.
Considering that the Z51 Corvette, at about $15K more adds quite a bit of performance, I don't think Chevrolet would be too worried about any kind of Corvette model shift. While adding the 505 BHP LS7 would likely make that gap much smaller, there is always that "prestige" thing with the Corvette.
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As for AWD on the Corvette, its something thats still up in the air. The die-hard Corvette guys (like myself) on GMI aren't too into the idea of it being on the "affordable" sportscar. But, much like the 911, we do recognize that a couple different models wouldn't hurt at times. This being said, I can see it happening on the next-generation XLR long before it shows up on the Corvette. That way the price increase would be better-justified, and at least in the company of the R8 and whatnot, it would appear to make more sense.
It will likely depend on this whole FM/MR debate, and my guess is that if the Corvette remains FM (as it should), we won't see the formula altered too much in the future...