Seeing how peopled ponied up alpha screenshots of star craft, and I use to have one of homeworld 1, it is not that unusual for companies to show work in progress. When I use to subscribe to PC gamer the previews were full of pre, alpha, and beta shots. It is not a rare practice.
As I said before, you can not compare well across genera to evaluate the knowledge claim of being par, sup par, or whatever. You are comparing very different methods on texture optimization, mesh optimization, lighting rigs, shaders.
Now the screenshot with the ms pain arrows is quite telling of your vantage point. 1) Terrain overlaps into other "hexes" Based on the progression of civ 1, 2, 3 and to 4 this is intended to improve the seemless look of the world (the hex grid is probably off by default as in civ 4). You also point to things going into the ocean. This is the only valid observation so far. I do need to point out that game development is an iterative process. Just because this is being shown in no way means those aspects of the graphics engine are completed. Expect at least one to two more iterations before the game goes gold.