I have not used Bamboo but I have used Hudson, Cruise and TFS and out of all of them Hudson was hands down the best. It is ridiculously easy to set up and has a really nice web GUI for project configuration. What is great about Hudson is that it supports pretty much any language and feature you could want assuming someone has written a plug-in for it, which they probably have.
http://wiki.hudson-ci.org/display/HUDSON/Plugins
We used it to run .NET, Java and C++ builds on timed intervals as well as SVN checkins with automated test harnesses and it was great. The place before last I worked at started some iPhone development just before I left and I believe they were using Hudson for that too.
Plus it's free!
