I thought that I might experiment, yesterday, with the recording of video in SL, and thus I did so.
I have no other tool to record with apart from the built-in "save to movie" option, which I find is somewhat lacking. Whilst it will record, unless the window is set to an extremely small size, for me at least the results are unusably jerky or fuzzy. What is more, it does not record sound. But it does work, at least.