There has been a CPU with transactional memory running big business servers. The Vega boxes from Azuul (~800 cores) running their JVMs. I know of two good internet discussions available talking about their real world experience using them
Gil Tene https://groups.google.com/forum/#!searchin/mechanical-sympat...
Cliff Click http://www.azulsystems.com/blog/cliff/2009-02-25-and-now-som...
It can be enlightening to hear from a real application of these technologies. I am sad to see it disabled. Had it in the back of my head to play around with it some time.