The Gamespot review is in..

"Galactic Civilizations II is a strategy gamer's dream, boasting a rare mix of depth, customizability, humor, and replayability. "

This is one of the most in-depth reviews we've seen yet.  Gamespot was one of the first places the review copies were sent and it is clear from reading the text of the review that they played the game thoroughly. 

For example, the reviewer even touches on how the screens themselves are moddable (using DesktopX):

While there is a plethora of game features that we haven't mentioned here, such as a galactic United Nations that raises issues that all races vote upon that impact your empire, extensive trade and diplomacy with other races, and much more, one that is worth highlighting and that follows the thesis of letting you have it "your way" is the completely open nature of the game's user interface. The game screens are stored in a directory and can be easily modified. The game is also designed such that there is no limit to the polygons it can handle; users are already showing off incredible Star Wars-based ships with extremely high polygon counts.

It concludes with:

One of the greatest compliments is the comparison to Civilization IV that many people are making. Suffice it to say that Galactic Civilizations II is different in many ways than Civ IV, but stands next to it as one of the all-time best 4X strategy games.

The Gamespot score is 9.0.  Gamespot rarely gives out ratings over 8.9.  In fact, Gamespot has not given a PC game a 9 or better since last October -- when it reviewed Civilization IV. 

Check out the full review.