Yep, it's the actual size. There's a lot of tiny, minimal cursor themes out there, and I'm a fan of the general concept. I decided to give a bash at making my own. It's a bit of a "challenge", seeing how many pixels you can shave off and still make it usable. I think though that this'll work best in lower resolutions.
As for BB themes, I've made a few... thanks for reminding me, I'll post 'em here sometime