I know NAnt sees frequent use (well, I always use it for my CI builds) but there has been no new official release since December 2007. Is the project receiving active development any more or is it dead-pooled? It worries me that if I carry on using it, and it stops tracking the latest version of .NET, I'll eventually be left with a massive job when it comes to upgrading systems to a version of the framework that it can't build.
Has everyone else gone over to some other tool like MSBuild these days?