I've finally completed putting the polyurethane on the sides, front, and second control panel tier. Below are some pictures of the completed pieces. The first is of the control panel (minus the T-moulding), and the second is of the sides and front pieces.

The next things on the agenda are to create a platform to position the TV at the correct height and angle. After that I need to attach the side panels and the front piece.

The compressor and spray gun arrived and I've put the first two coats of polyurethane on the arcade pieces. At least so far, I LOVE the spray gun. It's faster and it puts a better coat on than using a brush. I have to say this may have removed my distaste for finishing since now I don't have to worry as much about marring the surface with an errant brush mark. It seems like with a brush no matter how hard you try you'll mess up one of the coats of polyurethane; with the spray gun it's much less error prone. I'm trying to reserve judgment until I'm done (in case the final coats don't look as good or something), but so far I'm very impressed.

I don't have any pictures since I don't think they'd show much visible difference from the last ones.