Today I will mostly be watching the Student StarCraft AI Tournament. It's been running every year since 2011 as a challenge to student AI developers. The idea is that students submit bots to compete against each other playing 1v1 Brood War matches.
The games taking place right now form the competitive phase of the 2014 tournament. 42 active bots, all programmed in C++ or Java will play a total of 861 games between each other.
The conditions for winning and losing are slightly different than for a human Brood War face-off. The bot will be defeated if it loses all its buildings, if it crashes or if it slows the game too much. Victory is achieved if the other bot loses or if you have the highest in-game score after 90 in-game minutes. No word on GGing as I've never seen it happen in these matches.
The current leaderboard has Martin Rooijackers in first place with 17 wins and a single loss. He's using LetaBot which uses a number of strategies as Terran.
A post on TeamLiquid under the name LetaBot (which I assume is Martin) added, "I didn't have time to program the marines to finish the game after a bunker rush. Instead I used Wraiths that scout the map at random and attack any building that comes into their sight. Hence the name LetaBot (Leta was known for his Wraiths)."
Other names to watch out for are Soren Klett, Dave Churchill, Tomas Cere, ICElab and Krasimir Krystev - all of whom excelled in 2013.
You can watch the remaining matches over on Hitbox. After the tournament they will continue the stream with the bots playing for fun.
Oh, and here's the 2013 TvT mixed final between ICELab and Krasi0bot.