Just a note about the kgsGtp program that lets GTP-based go engines to connect to KGS. The new server was realeased today, it is now possible to play rated games on KGS. The GTP client is at http://www.igoweb.org/~wms/upload/ still. I will move it eventually, but for now that is the address to go to.
The client includes a manual on using kgsGtp; the manual also includes information on how rated games work. You need to get a special account on KGS to play rated games via GTP, just email me if you want to do this and I'll be happy to set the account up for you.