"I am curious as to what MMOs you've played in the past?"
I honestly will not be able to answer this fully because I will not remember them all. Easiest way for me to answer this is that I've played a lot of free-to-play mmo's, some mmo's most people haven't even heard of, and a lot of the major ones as well.. So.. Too many.
"Have you played WoW or Everquest?"
I played WoW for about a year (off and on) and I've played EQII, but not the first one. I mainly played WoW as something to do and didn't take it very seriously in terms of gear and raids. I joined WoW pretty late, so there was far too much for me to catch up on. EQII was fun as I was playing it with friends, but once my friends stopped playing it, I did too.
"Do you think Everquest Next, ESO, or Wildstar really have a chance of dethroning Blizzard as MMO champ?"
I honestly think Wildstar will give WoW a run for it's money. WoW will always have it's diehards though. I don't think Elder Scrolls Online will get as popular as Wildstar or WoW because people are acting like it is the first MMO to have a payment model, but I am equally excited for it. I'm a huge Elder Scrolls fan and have been since the late 90s. I also really like how much it is still an Elder Scrolls game, while still being an MMO. They are executing it quite well. They also seem to be taking tips from the popular Skyrim mods, which is awesome. I also feel it will have a more mature/older playerbase. Everquest Next is pretty much at the bottom of my expectations for upcoming MMO's because it will be free-to-play, and I've lost all faith in f2p MMO's. They're already trying to get people to pay for beta access before even giving any keys.
"Will any of these, or one ever for that matter, be a subscription based game going forward?"
Sorry I don't fully understand this question :\
"What are some features, gameplay, content, really anything that you think could make a great MMO?"
One of my biggest requirements is open-world PVP. I love the random encounters with someone I could beat up, or could beat me up. Keeps you on your toes. As for content, end game is always important because everyone hits cap eventually. And as for that, I think there needs to be something other than gear grind, or at least something alongside gear grind for end game. Maybe something a little bit more lore-based? Another thing which I think would be beneficial in this day and age of MMO's is graphics. And I mean demanding graphics. The reason why I say this is not just for something pretty to look at, but this also helps refine the player base to mainly those who had built their gaming PC, resulting in a more mature playerbase.
"What MMO did you play the most, what kind of character did you play?"
Sadly I think the answer to this question is WoW. And I haven't played that for a few years. There was a time period where I only had a laptop, and it wasn't for gaming; WoW was one of the few games it could handle. I started off with a Tauren Druid, and eventually created a Worgen Death Knight. I always prefer beast races.
"Bonus question, any speculation on Blizzard's "Titan" game?"
I think they're just going to use it as a cock tease for their playerbase for like 10 years before they even show any gameplay. Blizzard loves hype.