I used to watch a lot of screencasts in the past years because of ~1 hour bus+train commute to work. It's a great tool to check out new things, or to get a fast intro. In this way, I enjoyed the New Relic screencasts - they were more about the general idea of how things work, not specific implementations.

For figuring out how to do something, I find Railscasts great. But that's partly because when I want copy/paste and search, I can always go to ASCIIcasts.

So, to for your problem: I'd like to be able to watch a screencast explaining the general idea of the app and a quick intro to developing with it, but for the specifics, stick to text.