@Zapro: Aha, I've seen your blog before! This article made me remember: http://www.blog.zapro.dk/?p=121
I use Eagle; you seem to have far more and versatile experience than I do; I'm somewhat of a beginner with PCB design -- BTW, your latest project looks pretty fun. I've played with the TLC5940s, but they consumed too much standby current (no sleep pin) for my current project, so I stuck with shift registers.
If you wish, please shoot me a PM with your email, and I'll mail you a couple of boards soon as they're ready!