After one quarter with a tablet it has been useful for what I thought it would be useful for: helping students when I am away from a computer (say, in the reference collection or sitting at a table in the Learning Commons) and in meetings. This doesn't suprise me since I have been using my personal iPad for similar tasks since I've had it.
But after one quarter with the Nexus, do I like it? Not really. I like the mobility, but I have really grown to dislike both the dimensions of the screen and the Android operating system. I didn't think there would be that much different between using Android and Apple's iOS, but there was just enough difference that it bugged me. The keyboard is just different enough that I hunt and peck. Some apps I want to experiment with in Android aren't available. And, really, when it comes down to it--I just don't like it.
Some of my dislike of the Nexus is nothing more than personal preference, but if we were to purchase tablets for use in R&I, I don't think the Nexus or any other Android device is the right way to go. And my reason is based on my what a lot of people like about it: It's flexibility. While it is nice to have flexibility to set things up they way you want, the iPad is, honestly, more intuitive. And easier. And nicer.
But maybe that's just me.
I'll keep using the Nexus for as long as I have it, but based on some more recent experiences (it's been crashing; I had problems after I changed the password on my universal login), I'm not a fan.