A/B framework for Rails 3?

Is there anything like ABingo or Vanity that works in Rails 3? I know there's Google Website Optimizer, and Visual Website optimizer, but I need more power w/ regard to determining what is d开发者_C百科isplayed, and what is in turn tracked than they can provide. If not, I'll even take thoughts on frameworks that are relatively simple enough that I might be able to convert them to Rails 3 compliance easily.

Andy Atkinson has written Rails 3 Getting Started guides for A/Bingo and Vanity.