I'm a Wikipedia fan for a few reasons.
First, I like that it contains a history of the edits, this reassures me of some validity of the content and allows me to explore the controversies. I question the notion of vandalism and the concerns, what is vandalism and what is subjective opinion? Obviously there is a place for opinion and thoughts, it just becomes a matter of conditioning the on-line population to properly distinguish and post these things.
I like the opportunity given for people to post their knowledge, whether or not they are considered experts. I like the community that seeks to refine the postings. I do not yet have an opinion on the posting of anonymous edits, but I have decided to enroll as a member. There seems to be some level of indignity among the active community, I don't like that, but I generally like people, even indignant ones.
I like the vastness, the comprehensiveness, and the success of Wikipedia.
I like the WikiMedia engine. I use it personally for my own purposes.
I like "free".
- Math Inclined