But online, when creative affirmation finally arrives, it takes a very different form than it has in New York. In the offline world, getting a “big break” is a matter of impressing a subjective intelligence, one person or a few people who look at work with an experienced eye and declare there’s something to it. Up until now, it has been intimate encouragement that has literally set the course of whole careers: a gallery offers a show, a record label dangles a contract, a prospective boss plucks one résumé from a sheaf, and a path forward is set.

Such moments of recognition, by individuals or small groups, have helped to decide not merely who succeeds but at what. A nice note from a famous poet can cause an amorphously creative young person to throw the novels and screenplays overboard and take up verse for life. Without intervention from The New Yorker, John Updike might well have been a cartoonist, James Thurber a journalist, William Shawn himself a composer.

On the Internet, however, it’s not one single subjectivity but a popular hive-mind that decides. The “big break” arrives when, with lightning speed and often to one’s own surprise, the inscrutable pack decides to start forwarding one’s content around.

Like the note from the poet, the viral blowup online is transformative: The Gregory Brothers, transplants to Brooklyn from Radford, Va., are a serious soul band, but ever since the sudden success, this spring, of their deliriously funny YouTube series “Auto-Tune the News” (which turns news footage of politicians and pundits into pop jams), they’ve been devoting ever more time to keeping their hundreds of thousands of online fans entertained. Talk to anyone who makes culture online and you’ll often hear a similar story  of the first Web site that took off, or the video or the new meme successfully disseminated.

And so the move online changes how we make art, but the road ahead there is uncharted and perilous. In the old model, young creatives dreamed of entertaining the millions, but in practice they could do so only by first pleasing a small group of gatekeepers: established figures who controlled access to the audience and, in doing so, protected young people from that audience, its obsessions and desertions, its adoration and its scorn. These old hands had to worry about the numbers, of course, but they rationalized the upticks and downticks through a certain set of professional values, which they themselves spent years imbibing and which they in turn pressed upon their wards.

Online, though, the audience can be yours right away, direct and unmediated  if you can figure out how to find it and, what’s harder, to keep it. What to you is a big break is, to this increasingly sophisticated and fickle audience, just one forwarded e-mail message in a teeming inbox, to be refilled again tomorrow with a whole new slate of distractions. “Microcelebrity” is now the rule, with respect not only to the size of one’s fan base but also to the duration of its love. Believe it or not, the Internet is a tougher town than New York; fewer people make it here, but no one there seems to make it for long.