Would you guys seriously use it? Wouldn't you get annoyed with it after a while?
I regularly (usually once a week) change the skin I'm using. I see how other skinners have done things and store ideas away for the next time I make a skin. I also update .xmls if I see an included skin that's not 100% right with some of the 2.1 changes. So, I'm probably in the minority in how skins are used.
If it was implemented as an option to just randomly select a skin from what you have available, not change every time MB is restarted, I don't think I would get tired or annoyed with it.