sgolds, smooth20 - It is by no means a certainty that AMD or anyone else will have to deal with the issues of 3GHz+ operation. There are other options, multiple cores, for one. Entirely new approaches and architectures. Yes, until those are discovered/invented, we'll likely keep plodding down the path of greater clock speed. But things can change in the blink of an eye in the tech world. And we often don't see the change coming.
Paul