Just wanted to add that if you don't regularly have the free-time to commit to a full game of Go, or if you simply prefer to play at a slower pace, you might also check out http://www.dragongoserver.net .
They have a variety of board sizes, game types, and recently added tournaments. The average game will play 2-4 moves per day. I typically have 15-18 games going simultaneously, which overall gives me just enough to do while waiting for dependencies to download or the CI server to run.
One note of caution if you've played on other servers: DGS's rankings are shifted considerably higher than many other online servers (much closer in parity with the professional organizations). More info here: http://senseis.xmp.net/?RankWorldwideComparison
OGS (https://online-go.com/) is pretty good as well. It's web based and supports both correspondence and real time games. It's also pretty close to KGS in terms of features.
They have a variety of board sizes, game types, and recently added tournaments. The average game will play 2-4 moves per day. I typically have 15-18 games going simultaneously, which overall gives me just enough to do while waiting for dependencies to download or the CI server to run.
One note of caution if you've played on other servers: DGS's rankings are shifted considerably higher than many other online servers (much closer in parity with the professional organizations). More info here: http://senseis.xmp.net/?RankWorldwideComparison