People want to compare TERA to GW2, and that's irrelevant. Guild Wars 2's story I can actually understand. I know what's going on. The world events are amazingly fun? Why? Well let's see. I logged out of the Town of Nageling when a level 18 champion giant (me level 17) broke through their steel gate, I had to leave for work. I assumed "Well they're gonna defeat it and it'll be fine". No. I came back after 12 hours and nobody else tried killing it. Every single NPC was dead and I had to be lucky because I managed to get away without dying and it breaking my gear. A level 18 champion giant is the equivalent to a level 30 player and that's max level (I think). And I have never had so much fun just leveling up. I hate leveling up! But in GW2 it's enjoyable. If you can handle it, you can take anything with a higher level down, all it takes is time, effort, and skill enough to maneuver when you need to.
The Elder Scrolls Online I'm really looking forward to. No I don't know if it's anything like GW2 I'm pretty sure it's not. But I'll pre-purchase ESO also if there's an option. This may just be me, but I hope it kinda is like GW2 but adds even more fun. Again, I'm still going to buy ESO.
I have seen what an MMO model should be...and that's GW2. In my opinion.