With the softroot, a custom media application by craftycoder is available which is much better than the B&N audio player. However, due to the required softroot and the fact it may have to be installed manually on top of that, it's a little more demanding to get up and running. Screens and video
here. nookMedia supports browsing by album and artist as well as playlists, and additional formats compared to the B&N player. It's still being actively developed, though, so there may be rough edges.