In anecdotal testing, I've found that while Voice Control is very good at understanding the names of the people from my address book that I want to call, it's pretty poor at understanding artist, album, or song names.
For instance, when I asked it to play "It Was a Good Day," by Ice Cube (you know, the one where he didn't have to use his AK? I love that one), it instead began playing "Repeater," an album by Fugazi. When I asked it to play "All Hail West Texas," the great concept album by the Mountain Goats, it played my iPhone playlist instead.
Other users have reported the same behavior (a request for Bob Dylan led to hearing U2; Jill Scott resulted in Company Flow; "Eye in the Sky" resulted in M.I.A.), all of which leads me to believe that Voice Control needs some tweaking when it comes to music.
At least when it comes to speaking the name of the song playing (which you can make it do by asking "what song is playing"), the answers are correct.
I'd be curious to hear from you if you've had a different experience of Voice Control for music or if you've found any ways to improve its accuracy.
