I haven't played with the server yet, just looked at the demo server... And here is my wish list..
Does the build server detect individual changelists for VCS that support that? (SVN, Perforce)? Sometimes >1 change is done within check interval and the build server just builds all them together. My homegrown build server detects individual changes and builds them separately. It's strange why tools like CC dont' support that, it is quite useful.
Also, the history should contain VCS change number, it's much easier to refer to than time.