We trekked out to Harvard Bookstore today to check out the new print on demand machine (aka the book-making robot). I snapped some pics of the sample books they had printed out, and of the machine itself. Unfortunately the "print guru" wasn't in so I didn't get to see the machine in action (but don't worry, I'm going back out on Thursday for that, armed with a list of titles to have printed).
I think one of the most practical uses of this machine will be to get cheap reading copies of antiquarian / out-of-print titles - for $8 apiece, why not? Of course the same dilemma that you always get with Google Books is a problem here - if the scan is bad, the printed copy will be bad too (they'd printed a sample copy of Joseph Moxon's Mechanick Exercises, in which almost all the illustrations were partially obscured). So, before you order, I'd check the scan and make sure it's up to par, so you're not disappointed with the end result.
The covers are nothing special (just slightly heavier paper stock), but the binding's just about the same as any trade paperback book these days (i.e. not great, but serviceable).
I'll probably have more to say after I've seen the machine actually working, but so far, I'm intrigued.