Wikipedia lets any user edit, which means that a list of the most-edited pages serves as a proxy for controversy, obsessive interest, or both.
Ramiro Gómez put together a chart of the most-edited topic pages as of March 2015:
So what's going on with these edited pages? In some cases, it's about the level of controversy and the scrutiny a certain topic might receive. Some topics are always in the cultural ether (sample edit note for Adolf Hitler: "Undoing Colbert-based joke edit").
Other times, however, it can be based on a topic being extremely dynamic or inspiring a lot of passion. Measuring by Wikipedia edits, Michael Jackson could claim what the Beatles once did: that he was bigger than Jesus. (The Beatles, here, are merely bigger than India.)
Wonder why WWE wrestler the Undertaker is on the list? He may not be as historically significant as Hitler, but his fans' devotion more than makes up for it (sample edit note: "This is notable in that it was the first time he was seen as the Deadman without his long hair").
Overall, the chart shows that Wikipedia articles' edits reflect the esoteric passions of Wikipedians — a type of systemic bias that you can, of course, read about on Wikipedia.