According to a new poll from the Associated Press and CNBC, half of Americans think that despite Facebook’s popularity, the network is merely a passing fad. Not only that, but as the company has officially gone public, half of Americans also said that they think Facebook’s asking price is too high.

It’s not too surprising as numbers have been thrown around as high as $100 billion, which would make Facebook the biggest Internet initial public offering to date while valuing the company higher than Disney, Ford and Kraft Foods right out of the gate.

This valuation, however, isn’t completely baseless, as the social network boasts a user base made up of 40 percent of adults just in America alone who log into the site at least once a week. In total, about 900 million people around the world are Facebook users.

Facebook’s revenue has also grown from $777 million in 2009 to $3.7 billion last year.

Only a third of those surveyed think the company’s expected value is appropriate, while on Tuesday, Facebook lifted the expected price for its shares to $34 to $38 a piece from $28 to $35 each. But half of those surveyed think that Facebook is a good bet to invest in, while 31 percent do not. Americans who invest in stocks roughly agree, with nearly 40 percent saying Facebook would be a good investment.

For adults under the age of 35, the numbers are a bit different; about 59 percent say Facebook is a good bet. On the flip side, of those over the age of 65, only 39 percent say Facebook is a good investment.

It stands to reason that those under 35 would have a more positive view of Facebook as more people in this age group have been using Facebook since its inception, or since the site allowed high school students to join. Conversely, only about 21 percent of senior citizens use Facebook.

Despite the fact that Facebook is widely used by those under 35, 51 percent of young adults predict the site’s appeal will fade as time goes on, while fewer – 44 percent – think it will stick around as a service.  

This may have a lot to do with the downfall of MySpace, which was once the most popular social networking site for this age group, ultimately ousted by Facebook. In other words, history dictates that there will always be a next big thing.