I'll be using scrapbooking paper to cover the walls, so I don't know how much the dark (and, more importantly, differently-colored) plywood walls might show through. Therefore, I've slapped a coat of white paint on all the walls.
As you can see, the paint didn't take to the plywood evenly, although it did do a bit better than I expected (yay, Ceramcoat!). I'll need to put at least one more coat on it before I start papering. I made a bit of a mess on the floor but that's fine, since I have separate flooring to install. I like the color of the plywood; the stain I'm going to use on the floor should make it about that color.
I've also been busy painting the window and door so that I can pop them right into place once the paper's up.