Local colleague Liz Uzelac writes a one-side library ‘newsletter’ for patrons that’s posted in library bathroom stalls. Kind of clever idea, really. (Reminds me of my excellent undergrad alma mater library, which posted butcher paper in the bathroom stalls and invited temporary grafitti. And that in turn reminds me of all the writeable-walls and whiteboards I’m seeing in ‘information commons’ pictures these days.)
Anyhow, the most recent edition advertises a couple features of Umlaut for our patrons. See it here.
So, Jodi, that’s part of the answer to your question on what Umlaut does other than get you full text. Search inside the book; and finding similar or cited-by articles. So far.