As someone who has played most FPS games out there on the PC and swears by the mouse and keyboard combination, all I can say to anyone that says you can't play one with a pad is "you obviously haven't played Halo on the Xbox". They have got the control setup perfect and I feel as confident and deadly on Halo with the pad as I do on any PC fps with the mouse/keyboard.
As for it not being suitable, maybe yes as far as the realism and difficulty goes though the Xbox has Brute Force coming out soon and that is a four man squad based game. I recomend everyone scoot along to an Xbox site and check out the screen grabs and videos of this game, you won't believe those visuals are realtime.
While I'm on the subject of visuals, this would be OFP's main problem on Xbox... the average console gamer would not put up with those ropey graphics, far too PC and ugly. Though I think OFP is great, I have to say the texture work is pretty poor, the meshes for the soldiers are a bit questionable (whats going on with the chest area?) and the texture co-ordinates and cross polygon shading leave a bit to be desired. Dunno, maybe my grpahics card isn't working properly with it. Top marks for the density of objects though.