Is there a 'middle class' or 'Professional-Managerial Class'?

No Fate Project presents: Where’s My Jetpack?!

The idea of a middle class has popular currency, with everyone from factory workers to millionaires self-identifying as 'middle class.' Meanwhile, the concept of a 'Professional-Managerial Class' has recently gained currency on the left.

But is there a middle class? Is this the same thing as the 'petite bourgeoisie', or the 'Professional-Managerial Class'? What might the answers to these questions mean for those of us who aim to challenge class society?

More info at jetpack.zoob.net