Video Feedback with Viddler

For the last three weeks I have been using Viddler in my Listening & Speaking classes. We went to our wonderful computer lab and I helped them all set up accounts. We made a group for the class and did some practice recordings. I have had them do three assignments so far.
Our current curriculum for Listening & Speaking has task-based objectives. The assignments so far have been to record an invitation to a party, talk about your future plans and goals, and talk about a past experience. After the students have recorded their video, they give themselves feedback by annotating the video. Some of the students really do a good job, but I obviously need to do some student training. To be honest, I don’t give the best feedback either right now. Giving feedback to 37 students can be taxing.

Overall, I am pleased with viddler. What do you use to give students feedback on speaking?