I followed a little bit of this situation on the iMDB boards. Only a little bit, mind - I can only take such idiocy in small doses.
Apparently, after "The Dark Knight" toppled "The Godfather" from the number 1 spot, this incited torrents of hatred towards TDK on "The Godfather" forums. So, a bunch of the "Godfather" fans banded together to start a focused 1/10 campaign against "The Dark Knight" in order to restore things to "the way they should be." Part of why the average score of "The Dark Knight" has steadily dropped from 9.7/10 to, I believe, 9.3/10. This was accompanied by an influx of trolling on the TDK boards, from regulars on the Godfather boards. Bashing the film, bashing the fans, etc. Gloating that they'd ensure "The Dark Knight" wasn't #1 for long.
Evidently, they didn't count on the backlash of the "Dark Knight" fans voting 1/10 for "The Godfather" in retaliation.
There's no going back. We've changed things...forever. But, yeah, that's pretty pathetic, on both the Godfather and TDK fans' part.