Gameshark has one of the best previews of Galactic Civilizations II I've seen yet.

It goes into extensive detail on the new game elements and also talks about an interesting issue with regards to expansion packs.

One thing that many gamers new to Stardock's software may not be aware of is that Stardock doesn't just release software and call it a day with a couple of patches.  They get updated (for free) long after release.  These updates aren't just bug fixes but add new elements to the game.

Galactic Civilizations I, for instance, received countless updates after release that added things like Rally-Points, the Galactic Encyclopedia, and a ton of tweaks and enhancements that helped keep the game interesting long-after it was originally released.  Of course, the downside is that sometimes expansion packs don't have quite the same impact since players were getting so many free updates.

Still, in the long haul, we think that it benefits gamers and Stardock to release free updates that add new functionality to the game. 

For example, Stardock plans to once again release a free BonusPak that will be available for download upon the game's release.  We did this with Galactic Civilizations I and it did very well.  The BonusPak is essentially a series of goodies that beta testers came up with during development that weren't part of the game design but that we thought would be neat things to throw in later.

Because of the 3D engine, there's more opportunity to do more updates too.  For example, in most 3D games, the textures are bitmapped based.  As a result, if you go back and play one of those 3D games a couple years later, the graphcs look muddy compared to the "latest" 3D games.  In Galactic Civilizations II, our textures are vector-based which means that we will be able to keep updating them easily to higher and higher resolution. (see this screenshot as an example).

The idea being that even years from now, Galactic Civilizations II should continue to look as good as the newest games.  The 3D engine also doesn't limit the # of polygons used in a model. Modders can make .X models with as many polygons as they want.  And since the game is resolution independent (we've played it at 1920x1200 for instance) it isn't tied down by today's display limitations.

Now someone might make the argument "Well aren't you hurting sales of a future GalCiv? Why buy GalCiv 10 when GalCiv II looks fine?" but that brings up one of the key parts of Gameshark's previews: NEW VERSIONS SHOULD BE NEW VERSIONS.  A sequel to a game should be a real sequel, not a glorified expansion.  Gameplay, not graphics, should be what drives a new version of a game.

Read the whole article, it's a great read and highly informative.