It goes without saying the "true" RTS fan will be sticking around. My concern is how many RTS fans there are, not if they wil be playing HW or not.
I think there is not enough RTS fans, with an Xbox to keep HW going strong. I am willing to bet that atleast 95% of these true RTS fans are PC gamers. Perhaps alot of them own, or play Xbox, but it's not their main gaming console, so HW will be going weakly. Most of HW's audience is shooter fans, and they will be mainly playing on the lastest shooter. Us RTS peeps will be left with a game we can not fill with our few numbers. I've gotton all achievements in HW, spent a few hundred hours and had lots of fun with HW. I think MW2 release is going to be the final nail in the coffin as it where, for me anyway.
I'm just too competetive to play a game with less skilled players just fo the fun. The good players have left, so I will move on.
Anyway, HW will keep going. The RTS fans, and the FPS fans who want a break will keep numbers high enough to find games and enjoy the games they play. But the lack of competition is what will make me leave and hop onto the next RTS.
Arbiter is 1337!