Yea, a little bit old, but I recently bought it and I'm completely re-hooked on Galciv 2 again =( For some reason I just can't bring myself to get into Civ 4 again. Anyway, I don't know if I would call the expack changes groundbreaking per say... but some of them aren't too shabby either. I particularly like messing with some of the flashier ship parts and designs, especially since the graphics are improved a bit. Also enjoying the replayability of the different tech trees and some of the other differences the races have. The battles are definitely a little cooler as well with the graphics and some of the new sounds. Overall though, I think I just had a desperate hankering for a good space civ game and I forgot how awesome Galciv 2 was.

Here's the infos about Arnor:

http://www.galciv2.com/twilight/

I generally <3 Stardock, but this was and is their best franchise. I'm looking forward to their new medieval strategy game next year, but I can't say I'm 100 percent confident this will be beat.