It's a neat game. Looks like something that can kill some of my down-time this summer since LoL can go anywhere from 20 minutes to an hour a game. Playing a healer for dungeons puts me back into my PUG-ing mode in WoW.
My biggest complaint, though, is the targetting system. There's so many times where my cursor decides that I wanted to switch targets mid-fight, or thinks I'm aiming to heal that boss instead of the tank. The lag I can deal with since it's just a CBT and all--
My other complaint is the UI. I play on a widescreen laptop, so I have the UI pretty taking up my entire screen. It's mighty clunky. I wouldn't mind smaller fonts (personally, I think the current in-game font size is just a tad large), so I think an easy fix of compressing the UI is a good resolve. Another way to fix it would be custom UIs. If there are some out there, it'd be greatly appreciated if someone could link me?
The class system is pretty nice. Having played DOMO before, it's a much cleaner system than what they had in place. At least, from what I've seen so far (only got to CLv 7, so I've only switched between Warrior, Mage, and Cleric).