I don't work for Bandai, so I don't have any more information about the MusicStar than you do. Actually, I don't even have a MusicStar yet - none of the shops in my city have them in stock yet. If you have a MusicStar, you know more about them than I do.
Oh...hard question. But, I think...Don't they have they same characters as a tamagotchi v4 or v5? Sorry if not...the things just so new! But I hope I helped a little! Sorry if I didn't...
Actually, I noticed that the characters are the same from various other versions, same with the items and a lot of other things, but there's still new things! Best tama EVER!
Here is a page with the confirmed Music Star characters (Only the names in blue have info attached to them, so you have to hunt around for most of their pictures):