This is when it decided to penalize Rap Genius. Sure enough the site dropped in rankings. Rap Genius has been working on a way to get back into the Search Engine's good side.
Rap Genius co-founders admitted the wrong-doing, apologized to Google and recognized they deserved to be smacked down. Google recommends a 4 step path to fixing such a penalty and the company followed these exactly in order to fix the problem. After an extended analysis it took a lot of additional work for Rap Genius to cull a list of over 170000 inbound links which were not to Google's liking.
Reportedly the group wrote various scripts that eventually helped them go through all these links and eventually end up with 590 pages that were in violation with Google's terms of service. They even made their tool as an open-source program and published it under MIT license on GitHub so that anyone else could use it on their site also. The "Rap Genius Trackback Scraper" description listed on GitHub is the following: "This is the tool we used to scrape 178k URLs in 15 minutes in order to find which pages were hosting potentially spammy Rap Genius links. Given a list of URLs to scrape, it creates aggregate information that identifies the spammiest sites for manual review."