Couchbase releases are not in sync with CouchDB releases, the Couchbase server is based on CouchDB 1.0.1, the reason their versions arent aligned as Couchbase releases are not Apache CouchDB releases
So far, there are only mac builds (because I'm building them and that's what I'm deploying on), but Linux should come shortly and we should stop calling it alpha.
If you've got a mac and want to try out some new stuff, do this and complain to me about anything you don't like: https://gist.github.com/951106