I don't really know where to begin, but perhaps a good place to start would be to discuss the in-depth story this game has.  There is a SERIES of books based off of this game!  Sid Meier's as a company in my opinion did not do enough to hype this game, because this game is SO MUCH BETTER than civilization!!!  It's like civilization of the future!  They should take this game and ADD IT to the Civilization as a future technology expansion, like have different planets you could zoom into and run.  Isn't that really the next step for civilization anyways?  MARS!  ALPHA CENTAURI!  THE MOON!  Ect.  lol  There are a few things you have to get used to in this game, like for example, you can CUSTOMIZE yor units with different armor, weapons, ect. and they build fast/slower depending on how much they cost ect.  So you see how it can get a little tricky, but you can leave everything standard if you want.  Like I said this game has TONS of depth and in my opinion is BETTER than Civilzation 4 (which I have and am not happy with)  Civ 4 is too much hype and not enough game play.  It's fun, but Alpha Centauri just DOES IT BETTER.  This game draws you in and keeps you telling yourself, 'Just one more turn'.  Until 8 hours have gone by and you're thinking to yourself, 'Just ONE MORE turn.'  lol  I don't know what else to say about this game except I'm hoping to acquire the expansion pack and I hope that Sid Meier's gets a clue and makes a 2nd version of this game.