If you're a TechSmith Camtasia 9 (Windows) user and you move to the Mac, you'll be happy to learn that you can continue to use Camtasia. However, while Camtasia 3 (Mac) is similar to Camtasia 9 (Windows), there are several differences. For instance, there is no Library in the Mac version of Camtasia. While that’s a bummer (I love the Library), you'll appreciate the ability to have multiple projects open at the same time (Camtasia 9 is still in the dark ages… you can only have a single project open at any one time).
And you'll find some interesting features on the Mac side that do not exist in the Windows version. For instance, consider Share History.

Every time you Share a Camtasia project (via the Share menu), Camtasia Mac keeps a log for you. You can go back to the Share menu later and choose Share History. As shown in the image above, you review what has been shared over time, and use the hand-dandy Visit button to see the published masterpiece on YouTube or Screencast.com. (Note: You can right-click any entry and either remove it individually or choose Remove All Entries.)
The Share History feature might not seem like much given all the cool things you can do with Camtasia, but I find myself using it all the time!