Is Zynga's next game called Empires & Allies? Signs say yes

Remember way back in December, when FarmVille users were shown a CityVille billboard at the outskirts of their farms to promote the launch of Zynga's (then) newest game? It looks as though we'll be seeing another of those billboards in the near future, advertising what looks to be Zynga's newest game called Empires & Allies.

As of this writing, all details about Empires & Allies are incredibly slim, and we have very, very little to go on (basically, just this billboard). We know we'll be able to "build an empire," which leads us to believe that this could either be another take on the city-building genre, but with ancient buildings and architecture similar to Playdom's City of Wonder, or, it could even go so far as to be Zynga's version of an RTS (real time strategy game), created in an effort to beat 2K and Firaxis to the punch with their release of Civilization World.

Whatever the case, you can consider us excited. We're definitely keeping both eyes peeled for any and all news concerning Empires & Allies, and you can be sure that we'll make you the first to know everything just as soon as we do.

In the meantime, speculate with us. From what we've seen, what sorts of gameplay ideas run through your mind? For that matter, what type of game do you hope this becomes? Should Zynga create an RTS? A tower defense game? Another city-builder? Sound off in the comments.