How do the major gems play with this RC? Namely Devise, CanCan, etc.? I was going to play with the beta, but I think I saw some potential integration issues with Devise and I decided it wasn't worth the trouble.
Most of the biggest ones have been working for a while, or have a branch where they're working in support.
I think this is one of the biggest advantages of Travis' uptake in the Ruby world, actually: it's really easy to test your gem against Rails master and put it in allow_failures, which means you can know if your gem is compatible, and occasionally show when a new commit introduces an incompatibility.
If you find any gems that don't work, please ping me and I'll investigate and send PRs; this is one of the advantages of my employer (Jumpstart Lab) paying for OSS work. The whole Ruby world wins. :)
