I was just now going to work on this, although I planned on making an simple-but-maybe-interesting bot rather than a really good bot (specifically, I was thinking about making one that combined straightforward pathfinding and some reasonably smart local fighting ability with a strategy where I remember the median size of enemy ant "groups" and move ants near enemy territory only in groups of size N+1. I haven't talked to anyone about strategy, but after looking at the rules, I want to see how this does.)

I would have written this bot in Clojure on my lonesome, but I have sufficient expertise in C# or Javascript just the same, so if anyone is interested then let me know and we can work together instead!