Wordfence seems to be failing to recognize a brute force attack from an IPv6 address, probably from Ukraine. Here's the log: https://gist.github.com/as-com/9375146
The reason why I know Wordfence failed to block this attacker is because I never received a "blocked" email and an activity monitor plugin showed me those login attempts, and the attacker guessed some passwords that were...well, disturbing. Here is my (ultra-compressed 8-color) screenshot of the first page of the log: http://i.imgur.com/18hK5DS.png