Today is YouTube's eighth birthday, and to mark the occasion Google is revealing new statistics that underline what a cultural sensation its video site has become. Most staggeringly, over 100 hours of video are now uploaded to YouTube each and every minute. One year ago on this day, that figure stood at 72 hours per minute (it was 48 hours in 2011). So aside from record-breaking viewership — over one billion people now visit YouTube monthly — more and more users are continuing to upload their own clips to the site in hopes of creating the next viral phenomenon. YouTube has highlighted some of those memorable videos in its celebratory post, though at this point the greater challenge may be finding one you haven't already seen.