Karaoke ramblings.
I happen to run one of the oldest Karaoke businesses in the US. I'm a competent coder, but I'm still new to SL. I've been thinking about this issue in detail.
First, why do you HAVE to stream the singer? One of the fun things about Karaoke, is being able to sing. If we stream the background music and put the lyrics up "somehow", everyone could sing along. I agree it would be fun to have the official singer actually sing, but there is still fun to be had without that technological hurdle.
I haven't looked into the license issues, but I imagine that SL would just qualify as another, abet quite large, show.
I've got a huge catalog of computer readable karaoke, and a desire to put this together. My entire catalog is already referenced in a mysql database for online lookup of songs and printing of books. I'm a software developer by trade, and would be very interested in getting involved with building a virtual version of our club

This could be a L$ maker too. Imagine selling the resulting karaoke player that charges a fixed amount per song and pays the owner?
I understand that Japan has a similar feature for doing karaoke in 1st life. They have some service that has a central repository of Karaoke music, and bars pay a monthly service charge for access to the music and rental of the local networkable player. The back-end of this system may be able to be used for a similar 1st life system if licensing arangements can be made.
Anyway, this is what I've come up with so far;
We'll need an online repository holding all the karaoke music and the online database. It must be queryable for looking up songs. It must also respond to requests by a jukebox to stream a song.
We'll need a "karoake book" object that allows the user to look up a song. It will also need to be able to make a song request to the karaoke jukebox.
The jukebox must accept requests, perform some "standard" karaoke ediquette for singing order. It needs to identify if the Avitar that requested the next song has left the singing area and skip that request. It will need to be able to request that the song needs to be played, and access the streaming server. It must be tied to one or more karaoke monitors that will display the CDG lyrics. This may require a HUGE conversion of CDG/Laser Disc/DVD karaoke to some standard streaming format, or a major effort at creating a CDG playback facility inside SL. The jukebox must congradulate the last singer, and announce the next singer. I imagine the anouncements could be some combination of simulated voice from the server stream, or floating text.
I've got the hardware and the music to do the database side at least for testing. I imagine that the bandwidth use will be huge once this gets done. I don't have the storage or bandwidth access for the final product yet, but I imagine it would be worth while.
Please contact me if you are seriously interested in persuing this! I want it!