Beginning in February or March 2007, I became involved in my first significant content dispute on Wikipedia. This resulted from an editor who wanted (entirely appropriately, in my view) to add a "criticisms" section to the article on the book Lies and the Lying Liars Who Tell Them, but who was taking a rather unilateral approach to his article edits, and an increasingly hysterical tone on the talk page. Several editors had attempted to engage him in discussion, but he repeatedly turned the article toward personal disputes – while accusing other users of doing so – and refused to address arguments other editors brought up.
This dispute resulted in two edit wars. In the first, I warned the party in question about the Three Revert Rule, and he ignored my warning. I took no further action. The second time (a week or two later), I reported the incident, resulting in a 48 hour block of the page.
A few minutes after I reported it, the user in question filed for arbitration. The arbitration request was ultimately denied, on the grounds that intervening steps had not been taken.
Apart from the actions noted above, the dispute is generally chronicled at the article's talk page.
A positive result of the request for arbitration was that an editor (administrator?) volunteered to mediate our dispute. This resulted in a much calmer discussion, and appears to have led to at least some consensus on the page in question.
Another result of the process is that we learned that the user in question was the author of a web site he had tried, repeatedly, to cite in the article; this served to explain his otherwise baffling defensive posture. (The user has never affirmed nor denied his identity, but the evidence is strong, and he has let numerous direct statements of his identity pass without objecting.)
I haven't yet fleshed out my thoughts in writing, but I found someone who has, and I generally agree with her.