I create most of the screencasts with ScreenFlow from Telestream. This is a commercial screencasting software for the MacOS X. It has almost all of the features I need and the workflow is pretty fast and snappy. It records the screencast in an intermediate format. After recording you can select the cropping, zooming and other features of the screen record. You can activate audible mouse klicks and additional text captions, videos, audio recordings etc.
Only drawback in the current release is the slow export. Screenflow doesn’t use all the available CPU power to encode the screencast and thus taking longer to export as needed. But this seems to be a bug and will be fixed in a future release.