This is a quick update to note that TeamCity is on it's way to being supported.
I was given a patch for this and I am about verify that it works (it came from a trusted source through, so I am pretty sure it will). You know what the greatest part of the patch was?
It was one line of code.
<property name="version.build" value="${environment::get-variable('build.number')}" if="${environment::variable-exists('build.number')}" />
We don't even need a setting to determine if the build server is CruiseControl.NET or TeamCity, just one line to look for a variable and set our build version if it exists.
With this knowledge you shall build.