Ironically, for me the two best civ games of all times belong to another company (or perhaps companies).
Edit: If counting only this series, the best civ games of all times (for its time) is probably CivII followed by CivIV, CiV, CivIII.
I don't rank CivI because it was such a new concept so it (for me) automatically ranks the best in the series (although it wasn't the first game of its type).
I put CivIII last mainly because only remember rubber and when it came out it was so full of bugs that it was (almost) unplayable. For example I remember my first game, I was attacked by the russians, and he destroyed my entire country (units, cities, roads, etc.) because none of my fighters intercepted his bombers, because a bug in the game made that impossible (a patch came out a week later as a christmas gift). All the other civ versions I remember, although CivIV, although good, didn't become really good until BtS came out.
At least I tried to put a serious view on this, opposed to OP who (I think) only started this thread so he could say how bad he thinks CiV is. I think CiV is a good game with a lot of potential. Buggy, sure, but not worsed than other games I have seen and not worse than other Civ versions. Bad that a game comes with bugs, yes but thats the world we live in. You can get the feeling that it is more complaining now than (in general), that is because the net has become more social than it was before and people tends to only write when they are upset, not when they are happy about something.