I can't play any vids from cbs.com either. it says it's probably my adblocker. But just wanted to say i am using a hosts file, fanboys updated adblocker list, PLUS an auto-config script in lan settings, and my browser almost never bogs down or has the problems you mention. But i have other problems that don't make sense, so i guess we all have a little bit different experiences with it. Very much looking forward to version 7.
I'm really hoping Iron will use it's own gpu acceleration and it won't be a chrome add-on. At any rate. I think it's the best browser there is. Love this thing!