@kenbaldwin: Hi there! A couple replies for you.
Triggering: Yes, gphoto and gphoto2 are the right software for doing remote camera capture in linux. Unfortunately I was somewhat stymied trying to find cameras that are compatible and still currently available. But then, they also have multiple kind of supported cameras, from simply "capture" to "fully controllable". If you want to go the remote capture route, I'd love to hear more. I'm currently spending all my project-available funds on plastics and mount materials so I'm on hiatus from camera testing.
Command Line operation: Depends entirely on what version of the software you pulled down. If you've done a checkout recently you probably have our wxPython version. You can easily tell by whether or not you have page images inside the GUI. If you can see any pages, then you have the new version.
This is going to be our 0.2 release and is still currently in testing. At the moment I think the command line portion has been put on hold until 0.2 comes out, which will complete our transition from gtk to wxWidgets and also bring multi-platform support.
If you want to find out more, you can check out
https://edge.launchpad.net/bkrpr