Well, while I agree that a dev journal would allow others to benefit from my experience (and I might try that, but will probably experiment with a video format), it doesnt solve the original problem. The problem to be solved is: where can lone wolves (and small teams, startups) game devs find an environment to accelerate and facilitate the development process, a process which hardly existed 10 years ago (for single-person "teams"), and now is very much common. Without such an environment it's still doable, for example the way I described. But it's far from efficient. If there is a place where all the agents (programmers, artists, musicians, testers, marketing guys...) hang together, it's better for everybody. While it's hard for me to find good drawings to use on my game, or testers, or an artist to make the concept art, etc, I'm sure that for these guys it's also hard to expose their work.
My suggestions focus mostly on the forum, because I believe that having a big active community either solves most of the problems, or paves the way to the solution (since to have a properly working marketplace you need demand, and the forum/community would bring that).
What I'm talking about here is a market opportunity. Someone will eventually solve this. I think that GDNet is on a good position on this "race", but the biggest question comes back to: where does GDNet want to go?