I've transitioned to RAW in the past couple of months, and while I'm starting to develop a workflow, I get occasional surprising (to me) behavior. Is there a nice review of the thinking and backend behind the Darkroom UI?
http://www.darktable.org/resources/
The screencasts might be a good place to start, and the user manual is quite comprehensive. Disclaimer: I did some of the screencasts. Riley's course is a more-complete overview, but it's not free.
Also keep in mind that darktable just entered feature freeze for 2.0, should be released around the end of the year.