NOTE: There is an update not in the original report, apparently RG is working with Google to resolve the issue:

We are working with Google right now to resolve this. They’ve been really great, helping us identify changes we need to make, even on Christmas. We’re working on it as fast as we can, and expect to be back on Google very soon.

It sucks to be off Google for us and for the thousands of our community members who have worked so hard to create what’s often the best search result.

We hope everyone who reads this will take a little time out from their Christmas and head to Rap Genius and sign up so you can contribute your knowledge on your favorite subjects – becoming a member of our community makes the site way more fun. Merry Christmas