I recently finished the UI for the server browser in Overgrowth.
This will let you browse all of the multiplayer Overgrowth servers and easily choose the one you want from within the game. Check it out! (Note that the server names and such are just random Quake servers I found for testing.)
It's pretty straightforward. When you click on a server, it sort of pops out with an animation (you can see for yourself next week) and you can join the server. I'm thinking of putting some more info in the extra space that pops out, but I'm not sure yet.
We are really flexible with the UI. Are there any cool features in GameSpy, GameRanger, etc. that you'd like to see in Overgrowth?