GM is actually delivering what we've wanted for years with the 6thgen. They are going to make it lighter and smaller on Alpha, which is going to be a shared, less expensive platform. Zeta is a great platform, but Alpha will allow GM to save on production costs because the ATS is also on that platform. Alpha has been designed from the ground up for RWD and various engine packages, giving GM limitless flexibility for power.
Of course, the real concern is appearance, since the 5thgen is downright sexy. I have a lot of faith in the GM design team and expect them to evolve this car more than they change it. I would expect the Camaro to be very familiar with the 6thgen with appropriate upgrades and design changes.