Well, not actually -- they only got threatened with one. We heard from the site's founders, and they tell us that they got a call from Rod Rigole, a VP of Legal Affairs over at Blizzard, who told them to cut out using Blizzard's artwork and terminology on their website was a no-no, and that they would be recieving legal papers soon. Rather than pick a fight, they instead redesigned to the standard gamer dating site you see today.
But here's the kicker: they used an official fansite kit to actually make the site. Even with the stuff they give out, Blizzard seems extremely protective of their artistic IP -- they used this same technique to attack the WotLK wiki and the Glider folks as well. They'll let fans slide, it seems, but if you're making money off of their materials, beware.