I will keep the github repo in sync with the major releases of Web API (like Beta, RC, RTM). Because of the changes made to Web API after beta, my current bits don’t build against the CodePlex version anymore.
Today I installed a build environment for the CodePlex bits, and migrated my code. It turns out the changes are pretty easy: Simply replace Request.GetUserPrincipal() with Thread.CurrentPrincipal ;)
I will update the repo when RC comes out.