Chris that is very nice.. thanks for sharing the video and how you did it.
I have loopy HD and the Aiturn 4 pedal set. I think it's great. However I have not wrapped my head around doing this for a whole song, only to practice and play with it a bit.
the problem I have is controlling it smoothly and how to go beyond basic loops. I'd like to use it for longer tracks which is what I currently do with Garage band.
What I've done for recording (and mind you I'm just starting to explore multi track recording) is I use Garage band on my ipad with the Apogee Mic, or Jam input, and record several tracks (starting with a click track). once all the parts are set, I replay that through and amp all mixed in and then I video the main part I want to record... in the video from the link below I managed to switch (by adding two different videos) instruments for two different solos.
http://www.youtube.com/watch?v=iS2k0JAeKsE
What I like about this method is for instance even the Cajon (percussion) can vary through the song instead of just being a constant loop.
If I can find a way to do this smoothly in real time with Loopy HD I would love to try it... For now my focus is in recording good takes on each of the instruments I use for the backing track then a smooth video.
I think you can multitask way better than I can *grin*