Lady Gaga, Justin BieberThe music video is back again! After years of spiraling toward obscurity -- largely because of MTV's dwindling interest in acknowledging the "M" in its name -- artists like Lady Gaga have resurrected the medium with "event" music videos that get everyone talking, viewing and most importantly sharing. This April, Gaga's eye-popping, bed-burning 'Bad Romance' had the distinct honor of toppling Internet classic 'Charlie Bit My Finger' to become the most watched video of all time. This afternoon, Justin Bieber's 'Baby' dethroned Lady Gaga, only to fall back to its position at #2 (with no clear winner at press time) in some sick Internet fandom fight to the finish -- which goes to show you can never underestimate the resilience of a 12-year-old girl (and her ability to refresh her browser). So, who really deserves YouTube viewership supremacy? Watch and support your favorite after the jump.