A rather in-depth screenshot tour of the new KDE 4 beta 3 booted from a LiveCD.
Stephan Binner has released a new version of his KDE Four Live CD. This version uses a recent SVN snapshot and works quite well.
While I had some trouble testing the newest KDE 4 Beta release on my test machine, the KDE Four LiveCD works surprisingly well. According to Stephan the version used on this LiveCD is KDE 4 Beta 3 plus a set of recent patches.