We're keeping a small though sustained presence on the AEF server, but could always do with more players. I'm still not sure what's up with gamers here, there have been hundreds of FH2.3 downloads in Oz and only a handful of players online.
Yes, the co-op servers have become more popular lately. It helps to give that big game feel without needing to trawl in lots of players.
The AI isn't up to much on the BF2 engine, but its been improved drastically from vanilla. There are some single player / co-op fans on the FH public forum who are still developing improvements, some of which made it into the mod previously.