landed on the official Wrath of the Lich King page, and they look pretty different from anything we've seen about the next expansion so far. You can click on the pic above to see the first one full, and here's the second.
Now clearly both show a forested, lush area, and there is only one forest that we know of is Northrend so far: Grizzly Hills, supposedly a redwood type of forest home to the Northern Furbolgs. This forest, however, looks a little greener than that-- it may be the Sholazar Basin, which we haven't seen screenshots of yet. Obviously the creature above is some new kind of Dryad, so that means we may see traces of Cenarius in Northrend, and when you mention Cenarius, you have to mention the Emerald Dream. So we may find out more about that line of lore in Northrend as well. Very interesting.