Rogues, then, while not useless, are also not amazing. If you PvP, cool, you can trounce people. In a raid setting, you will have damn high dps (I cant top the rogue in my guild when hes with us, no matter how many trinkets i pop). However, your situational usefullness is limited. Your not going to be stun locking much of anything, unless you have a feral tank, expose armor wont help, so your down to dropping sin strikes, eviscerates, and slice and dice. So while ya, your topping the DPS chart fairly easily, your also not going to be as useful as a lock or a mage or a me, because we can pull stuff like banish, frost nova, and ZOMG ITS A CHICKEN! out of of arsenals.
So my verdict is: Not useless, but not usefull at the same time. Lit wins.