I think it's also important to take a step back and look at the entire competitive scene. It's DOMINATED by Non-shooter PC games. LoL, StarCraft 2 and Dota2 are juggernauts and aren't going anywhere for a long ass time. I think it's also important to note though this eSports is only going to go up from here on out. Competitive shooters will get bigger and better. And you could argue that CoD is already huge in eSports but that's just one game. I'm talking all of eSports shooters.
I think one thing where Bungie and now 343 messed up on is taking the hardcore fans for granted, at least to a certain extent. I think if you've got a really strong hardcore fan base that's happy, they're going to give your game legs. They're going to tell all their friends to play Halo with them. "Yo what games are you playing Tashi?" "Halo, StarCraft and Dota. Get them, we'll play. Shit is fun bro!" That's valuable. Valve hands out Dota2 keys like they're fucking Tic Tacs. I've given out like 5 keys to friends and family. I had extra so I gave like 6 to Ryaan for him and his friends. Everytime I play Halo with my old teammate I say, "Yo when are you getting Heart of the Swarm bro? We gotta play. I need someone to play with." He's going to buy the game really soon.