The Music app no longer respects album boundaries when you enter an album through Artists view. It treats all the albums under that artist as belonging to an implicit playlist. When you shuffle, all songs on all albums for that artist are shuffled and play. When you try to play an album, it doesn't stop when the album is over; playback continues with the next album. Here is a workaround, but please complain about the new behavior and ask Apple to fix it here:
http://www.apple.com/feedback
The workaround:
1. Go to Artists view, select an Artist with several albums, and start playing a song in the album you want to play. For example, at the top of Now Playing, I see "1 of 216" for a 13 track album, with the 216 being the total number of tracks for that artist.
2. Press the menu button in the upper right of the Now Playing screen, which will take you to a view of the single album with all its tracks, plus a Rating button in the upper left and a Done button in the upper right.
3. Press a different song, and immediately afterwards, press the song you want to start on.
4. Press Done. You're returned to Now Playing. I now see "1 of 13" for my 13 track album, and the playback is indeed confined to this one album. I can even press the Shuffle button to shuffle and play just the songs on this album. When the album is finished, I'm returned to the Artists view.