I have only played a rogue up to about level 15 in the beta so I can't really say how good they are at high levels. Although my 45 at the time warrior kicked the living hell out of a level 60 rogue in a defensive raid, the guy sucked.
It depends what kind of melee you wish to do, if you enjoy the sneaking around and attacking from behind a mob then the rogue would be the best choice, plus you get lock picking which I would love to have. Arcanite keys simply are not worth the bar of arcanite required. If you want to get stuck in bashing the hell out of everything and holding aggro then go for the warrior. I'm tempted to start a rogue myself at some point.