On the heels of its new MySpace Music venture, the social networking site has relaunched its MySpace Karaoke service as well.

Most notably, the service now includes a video recording function, where users can film themselves singing and post the video to the site. Previously, only audio recordings were possible.

In the six months since MySpace first introduced the karaoke feature, more than four million members used the service, leaving more than 500,000 recordings. MySpace senior VP and GM of MySpace Karaoke Nimrod Lev says he expects the number of recordings to expand now that video is available.

As part of the relaunch, MySpace will unveil a series of nationwide karaoke contests, hosted in partnership with such artists as Jesse McCartney and Seal. The artists will choose the winning karaoke versions of their hit songs, with the first kicking off Oct. 15-27 with Jesse McCartney. Seal will follow with a Nov. 11-24 contest.