I love Travis as well and use it on a lot of open-source projects I'm a contributor to, but I've been using CircleCI for private repos so far and really love what they do. I'd absolutely recommend checking it out: https://circleci.com/

It'll be interesting to see how the hosted CI market takes off - I thought CloudBees was going after it for awhile, but it seems they haven't pushed too hard, while there have been a lot of new entrants over the past year. Good time to be a developer, that's for sure.