Lately, I've been looking closely at build tools and, namely MSBuild and NAnt, so I stumbled upon this post from Don Box.

After some digging I came across the following thread where an MSBuild and NAnt integration/interop scenario seems to be in the scope of the work beeing considered by the VS Core Team.

I would say this is sort of a must-have for MSBuild, given the widespread use of NAnt.