Even easier, the only official Armory is at
http://www.wowarmory.com. Any other URL will be a fake. A Google of new armory could return either results as Blizz did add those features.
More worrisome is the sneaky emails I've gotten lately in my spam box. They are a direct cut & paste of actual Blizz "Somone has made changes to your account, if this isn't you click here"-style email. The links appear to be proper until you look at the actual URL, which is close, but just leads to keyloggers and such. They are getting craftier, I
almost clicked on one.