Ustream.TV has changed the way of broadcasting RTMP streams, so you may have problems recording because they do disconnect you.

The problem can be solved by capturing RTMP packets instead of recording. Replay Media Catcher 4 (Jaksta) in the RTMP recording mode (Go to Tools -> Settings -> RTMP Download Tweaks and mark the "Always record RTMP streams" checkbox) and Orbit Grab Pro can do that.

I'm testing a new version of WM Recorder that doesn't have problems with Justin TV and Ustream TV. Hopefully it will be released very soon.