Screencast Software Recommendations Needed

I'm looking for recommendations for screencast software on the Mac. iShowU looks promising and I'm going to check it out but I was wondering if there are any other applications I should also try? I want to find something that is simple to use and flexible enough to edit and export to different formats after recording.

On a side note and related to this, I'm planning on recording the Marketing for Mavens demo on Tuesday so look for it later next week.