One of the most enduring theories for a place we might see in a new expansion (besides the Emerald Dream) is the Undermine, home of the goblins. The Undermine sits on (technically, under) the Isle of Kezan, and where's that? In Azeroth's southern seas, right where our mystery blob is. Throw in the Maelstrom itself and a few more islands, and you've got yourself a pretty nice set of zones for an expansion.
So is Kezan what we're seeing in this picture? The theory is not without its difficulties. For one thing, the blob is way too big; Kezan is described as a small island, certainly not bigger than Northrend. But what if we flip the picture upside-down? This makes sense, because the bay in what I'm taking for the Eastern Kingdoms also cuts the wrong way, south instead of north. Then the mystery blob at the bottom becomes Northrend, and what we were taking as Northrend is now a reasonably likely candidate for Kezan, being much smaller.
Alright, I think that's enough unfounded speculation out of me. What do you guys think this is? Am I making far too much out of a tiny texture on a random book in a corner of the game, or is this the first hint of WoW 4.0?