Tigole confirmed last night that dual specs are currently being worked on. They are figuring out all the details internally still (which is a good thing). When a poster asked "I imagine by this stage we wouldn't see it until a patch after release?" Tigole replied "Most likely in a patch but it's not too far off."
Now you can interpret that different ways. Perhaps he means in a beta patch or a patch immediately following Wrath's release. Either way the fact that these dual specs will eventually be here will make many people quite happy.
Last night I was talking to some guild mates about it and the word that was thrown around was "game changing" for Protection Warriors and other low DPS specs. Since the Protection Warrior would just be able to flip into a DPS spec for farming, he would no longer need a farming alt – significantly changing the way the game is played.