A useful application on OSX I have found is Noteburner m4v converter.
Allows you to easily convert iTunes drm video to an open mpeg format that plays nice on a Playbook. Once converted just drag and drop file in the Playbook video folder.
Another nice built in feature is the Blackberry desktop app allows easy importing of your iTunes playlists.
So for me this is a nice mini black ipad! (Ok its not but I can dream.) When Apple realize 7 inch is the sweet spot for tablets I will buy one.