The RTAI developers are preparing to release a new version based on the magma branch. My first impressions are quiet good. They seem to have removed a lot of the unnecessary stuff, which makes the project appear somewhat less complicated.
The number of header and source files in the RTAI Kilauea tree determined with a simple find: 574. In the Vesuvio tree: 569. And finally in the new Magma tree: 325. Which shows that some serious cleanup has occurred.