I think it is actually working for HubPages. Look at their quantcast chart.
I have been doing the subdomain thing on a smaller level and it has worked for the most part, but I don't know if it would work if I rolled out my entire site with subdomains. The reason why I did the subdomain change is because I knew the reason why I was pandalized so I made the alterations to my pages months ago. I was waiting forever to get a new valuation out of Panda and it wasn't happening. As we know, it is not immediately updated. I had no choice, but to start rolling out some subdomains.
Again, this has worked on a smaller level for me, but I haven't rolled it out sitewide.
Has anyone else tried this? What happened with you?