As for closing threads on the 2K Forums: We are always exploring ways to make the forums a more useful place for people to discuss whatever they want to discuss. We invite all feedback, negative or otherwise. The threads that we were closing a lot last week were the countless "My personal review" threads we were seeing come up several times an hour. The problem is most of these threads were something saying mostly the same things that every other personal review was saying, and it was making it difficult for anyone to find threads that weren't the same thing as most of the others.
It's no different than you find here: When there were countless threads popping up about why this or that civilization is not included in the game, the moderators made the decision to create a single thread for this discussion and closed any new ones that were created. Edit: My mistake; it looks like these types of threads were forbidden completely for a period. It was Steam discussion that was asked to remain in a few main threads.
You didn't really answer the question... Long, well-written posts made by disappointed fans were deleted, posts like "OMG! This game roxX0rs!!!!!!!11111 Haters are too stupid to understand Civ 5, go play Civ4 and don't comeback you morons" were not deleted. I think most of the people that visit the 2k forums will indeed agree with me that people who enjoy the game don't seem to be playing by the same rules.
I've seen this so many times before. More and more users post negative topics, the company panics and remove them, with some bad excuse that there were too much flaming going on or something like that (often made by the ...fanboys... who get upset when someone writes something negative about the game). I've seen the same behavior on sports forums, game forums, movie forums... I guess you have every right to do it. But it's hard to take you seriously.