Also, there is no ZAM GuildWars2 forum here, why not?
Probably because of the forum on Guildhead. I assume they didn't want to split the community.
Guildhead was pretty nice for a while. Of course, GW2 itself has a /wiki function which brings up the GW2 wiki, so there's that. The only reason I ever go on Guildhead is to look up what weapons share a skin, and if they ever implement the ability to preview gear on the Trading Post, I won't even have to go there for that.
I noticed that on the GW2 subreddit (which is pretty active if you are looking for a GW2 community to chat with aside from the o-boards), someone was posting on occasions when there'd be a Guildhead update, but aside from those threads, there didn't appear to be any real attempt to become part of that community.
Honestly, it seems that the Zam Network launches a new site, promotes it a little bit, and that's about it. They don't end up getting enough user-added content to stay really up-to-date, and eventually nobody goes there anymore. Furthermore, launching each site as its own individual entity with little interaction with the other network sites is a bit short-sighted. They should be capitalizing on whatever community they have by making it easy to stay together throughout the various network sites. But what do I know?
Edit: It should be noted that I don't really fault those who actually work on the various sites. It just seems like a poor business model, and without proper staffing I don't see how you could really rectify it. Edited, Dec 11th 2012 10:43pm by Spoonless