The PC is no longer at the leading edge of computing, and Dean argues that services -- not another computing device -- are leading the way.

His argument makes sense: look at the rise of social networking. The service itself is key, not the hardware it's running on. This is true across a range of other computer industry sectors as well.

The PC Plus Era, Not the Post PC Era

Obviously everyone's not going to agree. In , Microsoft Corporate Communications Chief Frank Shaw says he likes to think of the current state of computing as the "PC-plus" era. He adds that over 400 million PCs will be shipped in 2011 alone.

"We'll continue to lead the industry forward in bringing technology to the next billion (or 2 billion or 6 billion) people on our planet," Shaw writes. "We'll do that as we always have, by working with our partners to deliver amazing experiences to individuals and businesses."