David Brancaccio: When stocks in the social networking company Facebook finally begin trading on Friday, the company will at that moment be worth a fortune. But that value will only be justified if Facebook makes profits for many years to come.

However — a new poll suggests that about half of Americans think Facebook is a passing fad, as Marketplace’s Gregory Warner reports.

Gregory Warner: A poll by the Associated Press and CNBC found that almost half of Americans think Facebook will fade away.

Jennifer Agiesta: There are some doubts about whether Facebook can make it.

Jennifer Agiesta is deputy director of polling for the AP. She says Americans under 35 are the most likely to think the Facebook IPO is a good bet. Though they’re also the least likely to have money to invest.

Agiesta: There are some things that younger Americans and older Americans agree on, but, Facebook’s not one of them.

The poll found that active investors are more skeptical of Facebook.

Zeus Karravala is an independent analyst of social media. He says Facebook might appeal to young people otherwise skittish about stocks.

Zeus Karravala: One of the things Facebook might do is get younger investors actually investing in the market.

But just because they may want to own a piece of Facebook doesn’t mean they think it’ll last. A slim majority of young people say Facebook will give way to the next cool thing.

Karravala: And there is a group of very young users that don’t consider Facebook cool because parents and other adults have started to use it. So I think there’s an argument that many of these things are generational.

Half of those polled say that Facebook’s asking price is too high. Which means it could be priced exactly right.

I’m Gregory Warner for Marketplace.