Is Dolby digital music still used?

Yes. You can purchase music dvd's with the data encoded in Dolby digital format - but it never really caught on, so the availability might be short lived.

--EDIT--

The original writer of the question stated that "You can purchase music dvd's with the data encoded in the Dolby digital format." I'm just going to go on a rant, saying that the apostrophe should not be in "dvd's." Does the dvd(s) possess anything? NOOO! Sorry, it just makes me mad that nobody in this country has proper grammar anymore.