Thanks, folks. I've downloaded Moon+ Reader Pro and am thus far very happy with it - though I don't like having to access the file system to pull a book into the device (it's not the intuitive, clean access that I want for books - though it's fine for podcasts and movies), so I think I'll download Calibre Companion so that I have that better, optimised display of my books. Thanks for your suggestions!

Something that I found interesting was that I had to download Android File Transfer to sideload files onto my tablet - I very specifically asked the sales boy if I needed any additional software to use the Nexus 7 with a MacBook Pro, and he very emphatically said "no!". Lo and behold - I plugged my Nexus 7 in today, and while it charged, it failed to read. There weren't any instructions in the box, either, so I needed to resort to Google to find out my options.

Now, I know that Android tablets aren't the most popular option for Mac users, but some of us aren't using a Mac with the belief that Apple is competent.