Claaarky, that's not true. That's all we hear about Panda is a) user metrics and b) thin content. Over and over and over.
What I've not yet seen, is evidence and recovery based on improved user metrics.
I appreciate you think you're on to something with exit rate and it's a nice feeling when you feel like there's some light at the end of the tunnel. But I seriously wouldn't get your hopes up. Certainly if your entire plan is revolving around user metrics.
I've read time and time again, that user metrics are being used, by SEO'd I have massive respect for such as Tedster, but where is the evidence? Case studies?
Panda has remained one of the biggest mysteries in SEO history.