I'm also wondering about the state of an open hardware approach. The well written arduino paper for the chi 07 conference in march (it's in the news archive) gave me the impression, that arduino is still an open project from any perspective. So I thought updated cad files would follow some day...
What's the real problem with showing the electric board designs? I really can't imagine that anyone would try to make cheaper boards from the files. But I guess that many would like to learn, adopt and shurly feed their own board designs back to all. I know by myself, that board layout is hard work, but there's also the arduino software, which is completley released and probably much more work.
Why differentiate and treat them different?
Oli