I am really loving this course and I think it's one of the best out there. The rss feed is a giant boost for me, as I need to have push technology push me to keep learning! Who has time to visit a web site?
On that note, email or twitter support would be great. My method for learning is to listen to a podcast 3-4 time until I get it. One of your competitors has a daily email with phrase of the day. If I could set up emails related to where I am in the course it would be awesome. For example, I could tag that I was "working on" beginner lesson 20. This would create a set of emails (or tweets) that would reinforce the vocab in different sentences. Being a web developer myself, I know this is a bit complicated, but it would greatly enhance the learning for me and would reinforce germanpod101's positioned as a tech leader in German language instruction.