Interesting to see some of the responses in this thread. I'm not the greatest MMO fan in the universe and certainly wouldn't hold TERA up as being some kind of game-changer. I also haven't played WOW for fear of being mocked and subsequently divorced by my other half. However, it does take its whole 'action MMO' thing pretty seriously, in that it genuinely can feel more like a Jedi Knight kind of game with all the strafes and dodges. They keep going on about how you only score damage when your weapon hits the enemy model, but that's either bullshit or an effect lost in the lag from Korea to the UK. Not that there is much lag, mind - no more than I'm used to from local servers.
The controller support works, and the emphasis on basic skill combos and evasions is such that I can see people getting deep into the game before they start itching for extra shortcuts. The UI is as cluttered (and often pretty identical) to the one in Aion: Tower Of Eternity, so much so that I've been happily playing the game in Korean with little thought for the language barrier. That said, I'm well aware I'm missing a vast portion of the game's more advanced features. I haven't been able to suss out the enchantment interface, for example, and haven't progressed to the point of mounts or pets.
There isn't the whole aerial combat thing Aion has going, which I'm personally grateful for as it means I'm not getting ganked the whole time. It's very solo-friendly, though while the boss battles provide AI assistance for players not in groups, the first boss instance in the beta is so fucked that one of the bots doesn't even move.
Tell you what else: for an Unreal game, this one really lets you explore. It's seamless, yes, with no loading times beyond jumping continents, but moreover it lets you clamber about the scenery as much as any sandbox action game. I've seen aerial city shots taken by folks who somehow climbed a nearby rock face, and my week-long trip round the continent consisted entirely of the sneaking past enemies who in Aion would have blocked off every bottleneck in the map. If you just want to travel in this game, there's absolutely nothing stopping you.
Best thing about that is that it dispels all the frustration you tend to get in MMOs where you feel you're jumping through hoops the whole time. It separates those offline RPG urges from the grind of a Korean MMO - though you tend to quest through this game more than grind - so you can indulge the first and then willingly succumb to the second. It's for that reason more than any that I'll be subscribing for a long time, I suspect, especially as you have to reach lvl 38 before you can cross to the next continent.
This could all be par for the course in WOW, obviously, but good luck finding comparable tits. There's no knocking Blizzard's art direction but there's also no denying that, when it comes to leveraging some of the strongest 3D tech on the planet to make a genuine artistic statement, this game climbs some way into to stratosphere before crapping on it.