<3 to GalCiv2, man.
My only 4X entries prior to this were MOO 1 and 3, plus Civ 2, so this was a huge improvement over any of that
But seriously, I've never seen a more INVOLVED dev community, and I compare Stardock (The dev, not the copy protection people) to Bethesda thus:
Beth is well known for their great support of customers through free updates and such (At least in Morrowind's days). However, for two weeks after OB's release, they AND their mod squad kept a blackout enforced on the forums, with no comments about bugs, suggestions to displeased users, notice that they realized what things were wrong with the game. In fact, the only thing they DID do was, when they realized that several video cards listed as being within the minimum specs could, not, in fact, run the game satisfactorily, they changed the Minspecs page without notice.
Sure, since then, they've given us overpriced armor.
But how about Stardock? Well, they have spent the entire time on the forums as they code. Seriously, I've known [company president] Brad Wardell to be awake at 2AM EST (They are stationed in Michigan, so I guess that was 1AM for him?) on the IRC channel for the game, literally implenenting AI suggestions into his code as we mention them.
They actively engage the community to create new mods and material for the game, and have a 750-reply thread about improvements we'd like to see, which they read daily and make comments on. The most impressive thing I've seen thus far is their work on the 1.1 patch (1.0X fixed nearly every bug that had been mentioned, even ones that affected tiny numbers of users). With this patch, they are adding in, and I do not kid you, PAGES of requested features. The ship designer is getting better, the AI is getting better, the graphics are going to improve. EVERYTHING
I have never seen a company be so involved with and so caring toward its customer base.
Jam it back in, in the dark.