So you've bought the game and you really like it but then time passes and it starts to get old. It's not that the game is boring or bad but that you have figured out how to "beat it". You crank up the difficulty level but then it's ridiculously hard to the point you know you have no chance.
If the game has multiplayer, you play people on-line but as you get further away from the original release, the harder it gets to find people and in particular the harder it gets to find normal people -- people who play the game as it was designed to be played as opposed to exploiting every minor game mechanic flaw to their advantage which tends to suck the fun out.
So ends the typical strategy game. It's usually a question of when, not if, the game reaches the end of its playable lifetime.
When we made Galactic Civilizations II, we budgeted some money for after-release work. We did go a little overboard with that with 1.1 and 1.2 in that the guys just never came down out of "crunch mode" and continued to put in crazy amounts of hours to deliver immense numbers of changes. Now things have returned more to a normal pace and so we look forward to 1.3.
Version 1.3 of GalCiv II will largely involve computer AI work by me. It's not just about making it tougher as much as it is about making it play differently and more intelligently. It will also likely involve creating additional difficulty levels and fixing the $@#$@ thing that causes some AI players to be set to stupid while others are at hard in order to average things out (i.e. someone setting the overall difficulty level to "Painful" only to find that 3 of the AIs are set to being really hard and the other 5 are set to being brain dead -- your best solution for now is to set the players you want to be intelligent or better if you're looking for a challenge and control the players rather than having the overall difficulty system try to guess what kind of gmae you want).
I have a lot of ideas on how to make the game play better, particularly with regard to the CPU option for the AI being able to use better algorithms. The expansion pack, Dark Avatar, will have a LOT LOT more of this kind of thing. But my job is to make sure that the AI continues to provide an interestig experience for players during the summer months.