Can anyone recommend some videos to me which explain the ins-and-outs of the chef and puppet configuration management tools? I have some familiarity with configuration management, having worked on cfengine (version 2) for a few years. However I haven't managed to evaluate the newer tools effectively. The barrier to entry (setting up at least a master and a slave VM...) has been too high (or I haven't given it enough time!)

If there are any good screencasts/videos that cover not just how they work but their individual advantages, that would be excellent: I have some upcoming time in which I can absorb material like that (but not the kind of time in which I could get hands-on).