[KarFan]

In reality GM is the one who set the bar at it's current level in the Pony car wars. The 2011 Mustang updates are Ford's very serious answer. The same way they upped the ante with the 3.7L V6 with 305hp and 30mpg is the same type of attack they will officially put down against the Camaro SS at the NAIAS in just a few weeks. GT500 news to follow. Ford is serious and so it the Coyote 5.0L project. They like many of us knew the return of the Camaro was long in the making and they had a good idea of what it would be packing so the 2011 Mustangs are their answer.
I've heard 412hp and just less then 400ft/lbs of torque as well. Don't expect the weight of the Mustang to go up very much either. Likely less than 100lbs over the current curb weight. That would put the power to weight ratio in Fords favor.

On Chevy's side there is a lot they can do to keep the SS on top. The suspension and IRS could use some further refinement and more performance oriented tune. The 6M needs gears. A 3.73 option from GM would go a ways in harnessing the power of the LS3taxed with moving over 4000lbs of race weight mass.
Maybe a performance exhaust option that could not only pick up a few HP but also drop some weight as many of the aftermarket systems have shown to do.
GM could put this all in a package something like Fords Track Pack.