its kinda a shame because sc2's custom scene is really lagging. Its over a year old, and there are still only like 5 custom maps that are heavily played, and they are all pretty primitive. They have made an elemental TD though, and its pretty solid. SC1's custom scene was great, but the map editor was kinda weak (although it was excellent for 1998).
But ya, the blizzard custom map scene peaked around 2002 to 2004. So many good TDs, arenas, random maps (again, i have to single out panda mansion), and rpgs (again, i have to single out video game rpg).
Anyone remember the tome hunter game where you gathered as many tomes and items on the map in a few minutes, then had duels to see who was the best hero?