Was going to wait for the next stepping or maybe Piledriver, but had the upgrade bug recently and got an 8120 for kicks. Still tweaking and seeing how far I can push it, but currently running 4.1GHz at stock voltage (1.3125V). More voltage doesn't seem to help much, though, looks like it might end up topping out at only 4.4-4.5 (was hoping for more, at least 4.6).
It's pretty much what I was expecting. Solid upgrade over an X4 955 in heavily threaded tasks, underwhelming lightly threaded performance, but what it offers is good enough for my needs and that Win 7 patch that's supposed to be out soon will help with that. And it's a hot and power hungry chip when you start overvolting, although it's not bad at all on stock volts (but this is on a D14, which is about the best air cooling you can get I suppose).