I've been in search of a new non-WoW MMO for quite a while now. While I think WoW is great, I can easily predict the future if I started playing again: I have fun for a while, play for about a month, and then quit due to the boredom of grind. So I wanted to find MMO that had gameplay borrowed from other genre's such as RTS's or FPS's. I'm still not sick of Starcraft or Counter-Strike because it's always fun challenge to improve your skill to beat great players. With RPG's your skill mainly based on your stats, and knowledge of the game, which is pretty boring to me. So what MMO's are out there that might have some different elements aside from the standard RPG?
In 2001, Shattered Galaxies was released. It had dated 2D graphics but it was still a blast. You had control of 6-12 units and you would fight to gain territory for your faction. You could join RTS-like battles of up to 30-40 commanders who each controlled a set of units. There are so many different types of units and they did a decent job of balancing things. Alas, I still eventually got bored due to grinding.
I also tried PlanetSide. An MMO mixed with my favorite genre: FPS. This game had so much promise to me. You could hop in all sorts of vehicles: aircraft, tanks, mechs. There was a quite of bit of weapons and armor your character could use as well. Unfortunately, I just did not have fun playing the game. Partly because it was laggy, partly maybe because I kind of sucked and died all the time, and the strategy for a race to win a large battle usually involved boring tactics.
A few weeks ago I stumbled on a game called AirRivals, which was an MMO that had Starfox-like mechanics for combat. The first several missions were pretty boring, and the dumb AI mobs never fought back. But I played until I got to about level 20, then things started getting interesting. Some of mobs started to aggro me when I got close and some of them flew in formations. I found myself having to barrel roll left and right to dodge all the missiles coming at me. Furthermore, I finally got a chance to PVP. Very fun. The graphics in the game are pretty decent. Since I'm working on Missile Defender 2, I'm using this game for ideas on what kind of special effects I want to put in the new version.
I would recommend checking out all the games I mentioned if you're bored. You can play SG and AirRivals for free, and Planetside has a free trial, I believe. They all have their strengths and weaknesses. I love AirRivals right now, but judging from experience, I'll eventually get bored of it and move on.