Step up from CruiseControl.NET to Continua CI. Define your build process in the browser with a simple drag and drop UI. With Continua CI, there's no need to edit xml to configure your build process.
Continua CI supports all the usual build tools out of the box, and includes support for Git, Mercurial, Subversion and many other version control systems.
Continua CI is built to be scalable, add mulitple agents and scale up when you need to.