The comedian Dane Cook apparently believes he is building his brand by pumping out a steady stream of comments on Twitter, the microblogging site that lets you broadcast 140-character messages to anyone who chooses to become your "follower." Cook's followers receive a regular series of bons mots: "Just got my hair cut. When finished she asked me, 'Do u want any product in your hair?' I said sure—how about dairy?" Or this: "The future is wide open. What a slut." Not laughing yet? How about: "I hollowed out the pages of a bible today & hid a smaller bible inside."

Cook's comments are so lame and unfunny that what he's actually doing is revealing, multiple times a day, how little talent he has. It's morbidly fascinating, kind of like the forbidden thrill you get watching Maury Povich's show or professional wrestling. You know it's awful. You know you shouldn't enjoy it, yet you can't look away. That, I'm afraid to say, is why I've come to believe that, of all the hellish things that have been spawned in the fever swamp that is the Internet, Twitter may turn out to be the most successful of them all—not in spite of its stupidity, but because of it.

Twitter has become a playground for imbeciles, skeevy marketers, D-list celebrity half-wits, and pathetic attention seekers: Shaquille O'Neal, Kim Kardashian, Ryan Seacrest. Sure, some serious people, like George Stephanopoulos and Al Gore, use Twitter. And a lot of publishing companies and bloggers (myself included) use Twitter to send links to articles we've published. But most of what streams across Twitter is junk. One recent study concluded that 40 percent of the messages are "pointless babble."

Then again, look at TV: fat people dancing, talentless people singing, Glenn Beck slinging lunatic conspiracy theories. Stupid stuff sells. The genius of Twitter is that it manages to be even stupider than TV. It's so stupid that it's brilliant. No person with an IQ above 100 could possibly care what Ashton Kutcher or Ashlee Simpson has to say about anything. But Kutcher has 3.5 million Twitter followers, and Simpson has 1.5 million. Who are these millions of people? If you're an investor in Twitter, you probably think, who cares? Kutcher and Simpson might be buffoons, but they've built bigger audiences than a lot of TV shows.

Yes, a guy on Twitter posted the first photos of that US Airways plane crash on the Hudson River in January. Yes, Twitter let the world follow the protests in Iran. And yes, Twitter users send links to useful news articles. But forget all the stuff you've heard from bloviating Web gurus about Twitter being useful, or important, or deeply revolutionary. For most users, Twitter is entertainment—a giant TV channel with millions of shows. Almost all of them are garbage. But a few streams have wide appeal. That's all Twitter needs.

A decade ago, media pundits were talking about "interactivity" being the next big thing. Their mistake was thinking that interactivity meant making movies where you could choose which ending you wanted to see. Turns out interactive entertainment is stuff like Twitter, where you not only watch others but can also have your own channel. In that sense, you could argue that Twitter is better than TV. At the very least, it offers a kind of entertainment that TV can't offer.

Twitter has been around since 2006, but it really took off earlier this year after Oprah Winfrey began using it. In August the site drew 25 million unique visitors, up from 2 million a year ago, according to Nielsen. Twitter takes in hardly any money but has raised $55 million in venture funding, and some pundits claim the company could command more than $1 billion in an acquisition. Until recently I've tended to dismiss that talk as hype-fueled Silicon Valley raving. But Twitter has rounded up a big audience at a time when audiences everywhere are shrinking. Dismissing Twitter's potential would be like looking at TV in 1948 and writing it off as a fad.