MOO2 is one of that elite group of games that has been continuously installed on the hard drive of every computer I've ever owned. As a Civilization nut who missed out on the first MOO, discovering MOO2 was just a bit like stumbling over the unannounced sequel to Civ that chronicled what happened after you launched that ship to Alpha Centauri (with apologies to Sid Meier's Alpha Centauri, another fantastic sci-fi TBS game). You simply cannot go wrong with this game.
If you like deep strategy in a sci-fi setting, engaging art and a deep research tree, and the ability to tweak every aspect of every one of your vast armada of battleships, this is the game for you. It has a great balance between development and combat, and you can change the game's and your species' settings so that your gameplay experience is perfectly suited to your tastes.
And now I get a treat, too, because I can discover the original MOO as well. I'm excited for it!