No, but I've been thinking of getting in to it. Also, this thread should be moved up in to the Starcraft 2 Maps, Replays, Modding section.
I think that given a year or so to balance it'll take the crown from DotA. The sc2 map editor is immensely more powerful and with the new tools and ideas it can become quite the hit. Needs time for heroes and lots, lots of balance issues, but if the makers are good with such things it'll turn out awsome, for the fans of the genre