Aye, I've got the 360 version but I rarely use it, I still prefer to play on PC but it's pretty cool being able to chill and play in my lounge on the sofa with my stereo on if I'm not doing much in-game.
As for control, yeah you can plug in any USB keyboard and it should just work, I use my old PS2 linux one.
I don't know if it supports USB mice too, never actually tried one. You could theoretically just use joypad alone but the on-screen keyboard would make chatting and stuff very, very slow.
BTW, with the last update they finally included achievements that can be unlocked. They seem to be pretty hard requirements too, I've only got 5 out of the 30-or-so they added, three for getting each nation to rank 10, one for having Paladin at level 75 and... get this... the last one I got is for having a craft at level 100!!!