Wikipedia and the Zodiac Killer

Zodiac, a serial killer whose identity still remains unknown, continues to make headlines, most recently in the murder of Megan Touma, when a newspaper received a letter from someone purporting to be the killer, who will "start using my role-model's signature". A friend on IRC noticed that the John F. Kennedy page on Wikipedia had been defaced with a message, purportedly from Zodiac. Within 30 minutes, the message had been decrypted:

vandaljzing wikipedia is so fun it is funner than killing people or having sex because when you kill people you only destroy their bodys but when you vandalize this website you kill the soul of the poor queer pig slaves that devote their lives to the embarkment that i am now destroying with my own bare hands

Rough timeline of events:

• Google indexed the same message in the William McKinley Wikipedia article.
• sbp noticed that there were 26 unique symbols, suggesting a simple substitution cypher.
• sbp provided a simple symbol-to-character hash, for use in online solvers.
• ianivs used a cracker to solve it in 6395041 attempts.
• The folks in #wikimedia found the template changes.