As a member of almost all the A&A forums, I might be able to shed some light on this question.
1st off, Dead head has got the main idea, it started back when the old wizards forum went under, and all the A&A minis players went there. Instead of a cramped wizards forum, they had a community driven program where the players ran the forum.
When I started playing A&A, I came here and fond some of the cool maps and other cool things. Then, when I got into A&A Minis, I came back and… the forum for AAM was dead! I looked for info on the newest set (Eastern Front), and instead found info on D-DAY!!! That was 4 sets ago! :o Well, not surprisingly, I kept on looking, I found the wizards forum, but it was basically dead, since posts only appeared like once a day. The my friend showed me the Forumini, I got the newest HHR, all the maps I could ever use, an easy mapmaking doc, al sorts of stuff. Let’s just say I stayed! :D Not only did it have AAm, but it has even more WAS stuff, tones of online games and 1000’s of pages of info. I don’t play WAS, but now that AAAF came out, I play that, and it’s got a good start! (I played the first ever AAAF online game)
Now there is the seasablaze WAS forum, the Underground, and I think there are quite a few Spanish/german forums around. All good forums, but the ForuMini is the largest, and has the most creativity.
Just saying! :D
-Rebel
A&AM Map maker