MICHELE NORRIS, host:

Seismic changes this week in the Internet hierarchy. Myspace.com, the online hangout for trend-setting teens, is now the most visited Web site in the U.S., according to the Internet monitoring firm, Hitwise. That means MySpace has outpaced online giants such as Yahoo and Google.

In case you've never seen it, MySpace is organized around personal home pages that are sort of like yearbook profiles, but punched up with music, blogs, and video clips. It has now become the space for young people to share music, art, and in some cases, seemingly every detail of their personal life.

Spencer Reiss has recently written a cover story for Wired magazine about the company's phenomenal rise, and his outlook now that MySpace has become part of the Rupert Murdoch media empire. Spencer, thanks so much for joining us.

Mr. SPENCER REISS (Contributing Editor, Wired magazine): It's great to be here.

NORRIS: Now, what's driving all this MySpace traffic? Is it primarily young people, and mainly in the U.S.?

Mr. REISS: It started as young people, and it did start mainly in the U.S., but as the numbers rose, and they are really phenomenal numbers. I mean, we're looking at 250,000 people a day signing up, and that's been holding pretty constant for the last six months.

So in fact, when we started this project, we were looking at 60 million people. By the time I think we put it to the printer, it was 80 million, and it's now up to 90 million. They're doing that entirely by word of mouth. That's one of the - I mean, most of this is people going to their friends and saying, hey, have you got a MySpace page? You should get one. And so people hook up.

It's not that you're really directly hooked up to 80 million people, although you could be if you want to. Mostly it's about being hooked up to your friends, acquaintances, family, and that's why they call all this social networking.

NORRIS: Now I don't want to get too deep into the weed on this, because I understand there are lots of ways to slice this apple, but is it really the top ranked site? Is there more than one way to look at this?

Mr. REISS: Well, yes there is. But things like Yahoo have a lot of different pages. They have a homepage, and they have other - and this is really just measuring one way into a site. And so I think the total traffic of something like Yahoo or Google might be a little higher than MySpace. But what's interesting about MySpace is that for a lot of the people that use it - and I think, you know, it again, it started out being young people, but it's broadened quite a bit, and I think it's kind of moving up to the 20s and 30s now - is that they spend a tremendous amount of time on it.

I mean, for some people, effectively, this is the Internet. This is people who are actually hanging around - which, of course, advertisers love, for one thing.

NORRIS: Now I like your description of MySpace. You say it's part nightclub, part shopping mall, part 7-11 parking lot.

Mr. REISS: Yes, I mean that - again, that's - you hang out there. You make a little change. And what's interesting is that you don't just change your own thing. Everybody has on their page a kind of a comment section that's public, and so you can go over to your friends site and see something that they've done and say, hey wow, love your new look and press the button and boom, and that gets put up on their page. So you're seeing what all their friends have said about what they've done, and that's what gives it that kind of hangout quality.

NORRIS: You described this as the most disruptive force to hit pop culture since MTV. Disruptive?

Mr. REISS: Yes, disruptive because the great magic in the entertainment business is how do you make a hit? I mean, everyone has their theories, you know - advertising, this, that. But word of mouth has always been the gold standard. The trouble is with word of mouth, you don't really know how it works.

Well, MySpace gives people a window into how word of mouth happens. You know, if you take a song or a band that no one's heard of, and you kind of roll it out, you can literally - on a thing like MySpace - track its progress. You can actually watch it happen, and the theory is that if you can watch it happen, you can study it, learn about it, and figure out how to reproduce that.

NORRIS: Now what's happened since Rupert Murdoch purchased MySpace?

Mr. REISS: Well, it's probably worth about ten times more than the half a billion dollars he paid for it, so he's sitting pretty happy right now. It hasn't actually changed that much from the way you look at it. And again, that's one of the things that you hear over and over again, both from the MySpace guys and the news corps guys, which is, we'd be crazy to change it. It works.

NORRIS: Spencer Reiss, thanks for sharing our space.

Mr. REISS: My pleasure.

NORRIS: Spencer Reiss is a contributing editor at Wired magazine. Transcript provided by NPR, Copyright NPR.