MY Mavericks installation ended up in a continuously repeated reboot loop. After I booted to Safe Mode I could see the crash info
that hinted about a nomachine product. And by removing the Nomachine app Mavericks would boot up correctly. This took me several hours to debug and resolve. I can live without that app for now. Probably in some future the fine folks at Nomachine will add support for Mavericks as well.
I can post the debug info if that is of help to understand the problem.