In fact, I have recently started wrapping up development on just such a thing. The site is new, so there are only a handful of users, but I hope it will develop into something more active in the near future.. Anyone can register and (of course) it's free.
The site also has journal "headlines" and a jobs board as well as a small collection of useful links.
Check it out, and feel free to register and contribute. Also, if you have any suggestions on how to make it better, let me know and I'll probably take your advice:
http://www.thetrainedeye.org
