But Beyonce is giving them all a run for their money.
Her video for "If I Were a Boy" has been watched by more than 34 million on the video-sharing site. In it, Beyonce imagines life if gender roles were reversed between her and her boyfriend (a fictional boyfriend, alas, not Jay-Z).
This offers the particular thrill of seeing Beyonce as a police officer - which, if it ever happened, would surely cause such a rash of speeding (with the hopes of a ticket from the pop star) that roads would resemble "Grand Theft Auto."
The popularity of "If I Were a Boy" is matched by Beyonce's "Single Ladies (Put a Ring On It)." That video has yielded at least 22 million views and inspired countless bedroom copycats.
Whereas "If I Were a Boy" is conceptual and has a narrative, "Single Ladies" is simple, imitable and iconic. It's just Beyonce dancing in a black leotard and heels (and a bizarre metal glove), flanked by two similarly dressed female dancers on a plain white studio set.
The video has spawned dozens and dozens of amateur versions, from the mimicking of a toddler named Arianna to more aggressively serious attempts, like that of a 20-year-old North Carolina native who identifies himself as a Staples employee named Chris or "Angel Pariz."
Beyonce has spoken about how bowled over she is by all the imitations and met some of the dancers. She also joined the "Saturday Night Live" parody of the video with Justin Timberlake and cast members Andy Samberg and Bobby Moynihan. (That video has also been watched by millions online.)
Beyonce and her record label, Sony/BMG, surely hope her latest video, "Diva," also hits a nerve. Released on Dec. 24, it returns the singer to the simple style of her and two dancers in a plain setting - this time an empty warehouse.
It's a grittier and less catchy song, though, and the video hasn't sparked the same attention, drawing less than one million viewers on YouTube so far.
But the popularity of Beyonce's videos only reinforce how important music videos are to the Google-owned YouTube. Many of the most watched videos in YouTube's short history are music videos. (Remember how OK Go's treadmill clip was such a hit in YouTube's infancy?)
Earlier this month, though, videos by artists signed to Warner Music Group began disappearing from the site after contract negotiations broke down between the music company and YouTube. The takedown included many fan-created videos, as well.
It's a somewhat ironic development for a medium - the music video - originally created as an advertisement to sell records (and thus something labels wanted played as much as possible). But as album sales have declined, all revenue streams are more important to labels.
At the same time, YouTube is aware of how much music videos are part of its lifeblood; the site promptly posted a blog entry explaining the situation to users.
There's competition in being an online broadcaster of music videos, too. Artist pages on MySpace increasingly host music videos, and MTV earlier this year launched the beta version of the impressive MTVMusic.com, a player that hosts seemingly every music video.
And naturally, Beyonce's "Single Ladies" is one of the most viewed videos at MTVMusic, too.