Since most questions here can have an unlimited number of answers, I think the automatic conversion to CW when a question receives 30 answers should be removed.
See also: Purpose of Community Wiki
I still fail to see any reason why any post should be CW here. We definitely need to do away with the automatic conversion, and I'm not even sure we need a flag.
I agree with this, maybe there should instead be a flag reason for a question to be made a community wiki...
I would love to be able to upvote this question, but the automatic CW conversion has actually kept me below the 15 reputation needed to vote. In a technical forum with specific answers, it helps to keep the answer count down, but in a more discussion oriented forum, where the answers are often opinions, it actually ends up penalizing people for participating.
I think CW makes sense for some questions.
For example, the "What features would you like to have in PHP?" question is well-suited for this: People can feel free to both submit their ideas and to down vote ideas they disfavor. Because votes don't affect reps you can see where the consensus is: what is popular, what is controversial (provided you have the ability view vote counts) and what is plain unpopular.
Without CW, there would be less freedom for suggesting ideas. Meta works similarly in this regard.