Here are my 5 reasons that I unsubscribed today.
1. No innovation. I know this has been said over and over again, but it feels like I am playing the same game over again that I had already left for something new.
2. Server population. Servers are drying up and I had to reroll on another server so that I could actually play with people and sell things on the GTN.
3. Bugs keep popping up. They say things are fixed in the patch notes and they are not, plus it seems like every time they fix something, then something else gets broken.
4. Dailies. Enough said.
5. Lack of character progression past level 50 besides gear. This is an MMO trend that needs to die a horrible death quickly. I am tired of the only way that I can make my character any more powerful is to get better gear. It would be nice to have combat skills to level up that take a whiel that make a marked improvement on my characters performance, or an AA system that gives you abilities that work in PvE only and not in PvP so that it remains balanced and yet still gives you something to work towards.
I hope that someone innovates soon, because I really love the idea of MMO games and being able to play in a living breathing world with other players who have similar goals as you. I hope that game comes along soon.