Can I shuffle a set of songs when I add them to Up Next?
You can option-click the shuffle button at the top of an album to queue it in a random order. Oddly, if I do that for the artist it only adds the first song in the list. Weird. And you can't intermingle different albums like this, you have to do that manually in the Up Next panel.

Correction: if you go to Artists view, select All Artists and then option-click the shuffle button next to one of the artist names, it will queue all the songs by that artist in a random order. If you select an individual artist and do it, it will only queue the first song.