I've been a Civ fan since I played a demo of Civilization II way back in the mid-90s in a big PC outlet in New York. It was love at first play. I still think that the wonder videos in Civ II are the best in the series, none of the crappy wonder sequences done since have even come close. I still remember the themes for Civ II Women's Suffrage and the Manhattan Project! I wish they would just bring back those videos, I liked them a lot better than all this computer generated crap.
I'm quite happy with Civ 5. It definitely has a lot of problems at this point, but, remember Civ IV when it came out? The AI didn't even know how to stack units. Whenever an AI from another continent declared war on me I'd just shrug and say, "oh, that's not a real war, they're on another continent". They'd just send one or two units on an undefended transport every 10 turns or so. Nothing to do with Civ IV now, where if another continent declares war you know they mean business! My last Civ IV game I had a huge navy prepared for incursions but the AI sent a stack of frigates with four galleons filled with deadly units to my border, THEN declared war and to my dismay punched through my formidable and well prepared defences.
With version 1.00 of pre-expansion Civ IV this was unthinkable, the AI simply did not know how to use stacks, embark units, invade either by land or sea. Version 1.00 Civ V AI is still way better than verson 1.00 Civ IV AI was.
I like the social policies more than civics, the hexagon-1upt system adds fantastic strategic depth though the AI still doesn't know how to use it (they just love to conveniently put themselves in range of my ranged units). The city states are a good idea, bad implementation, I find them a bit annoying, lifeless and repetitive. I suppose it's true to life for a superpower to manipulate a bunch of quarreling minor nations, but not enough is done with them... some scripts would spice them up a lot I bet.
The game has been released with an obscene number of bugs. I actually got one of the nastier ones: the Spanish XP no launch bug, and couldn't even play until last Friday when they patched it!
It's also a resource hog and has absolutely no optimisation whatsoever. But again, same as Civ IV when it came out.
I'm happy with Civ V overall and suspect that with the forthcoming patches, DLC and inevitable expansions, if it's improved as much as Civ IV was from its release, it will take its rightful place in the Civ pantheon.