Upvoted, I've been checking this out recently. As a codebase customer they sent me a free account to deployHQ and it seems pretty nice. It has an API (with a rubygem) so you can integrate it into your scripts to achieve whatever level of fancyness you need.

I'm also looking into the possibilities around having a 'deploy' or 'production' branch in git, and a post-commit hook that automatically deploys (with another script obviously) any commits to that branch. This is how heroku works and it's much cleaner than capistrano in my eyes.