Warcraft 3 is alive and well, which makes me incredibly happy.
And I think this ties in with the Mod theme of the title very strongly. I don't _love_ RTS games, I can play them but it's not my biggest hit. But the Warcraft III custom games simply blew me away. As a teenager with a fairly limited game budget I have gotten a ludicrous amount of enjoyment out of the countless hours I've put into Warcraft III.
I'd be surprised if you told me I've played the RTS/classical mode of the game over 30 hours over my life. But if you told me I've played over 4000 hours in custom games I wouldn't even bat an eyelid.
Heck, as I said even nowadays I still reinstall and play a couple of fun maps every now and then.
I guess what I'm trying to get at is that modding support is an extremely positive thing, and derivations of your creation can truly breed a life of their own which I can only see as positive for your consumers.