Watch out for the Facebook initial public offering.

This stock could hit a rocky patch within the next year or so as the social networking site now faces drags on its revenue growth and profit margins, while at the same time it will have to answer to a public marketplace, cranky shareholders, big investors and D.C. regulators.  

Facebook to me is a phenomenon of the economic downturn. It added hundreds of millions of people during the last decade when the U.S. saw not one but two recessions, the last the worst since the Great Depression. Economic growth is the worst since 1950.

People bunker down during downturns, they nervously log on and network to see about jobs, to check in with friends and family across the country, to do anything to feel better. Once an economic recovery kicks in, they may ditch Facebook to, well, make money, look for new houses, travel, work hard at their new jobs, you name it.

But now, as its expected offering price grows to a nosebleed 70 times earnings, Facebook is being valued as if the whole world will ditch their cell phones and landlines to only talk on Facebook, as well as only read news, business or entertainment headlines on the site.

Scary, because Facebook is built for the age of desktop or laptop computers, and not the age of mobile phones or the smart phone era -- which Facebook just basically admitted to in a recent filing with the Securities and Exchange Commission about its IPO. 

Meanwhile, on a price-to-earnings basis, Apple (AAPL) and Google (GOOG) are trading at about a fifth of Facebook’s asking price, and these two have multiples of Facebook’s revenues. Plus, Facebook faces growing competition from other social networking sites like Google and LinkedIn.

And let’s face it, the ad models for all Internet networking sites are creepy. Facebook trolls for information about you and your friends, which it then sells to advertisers or Internet game companies.

But to keep its ad revenues up (more than 80% of its total sales) Facebook has to risk alienating users by carrying even more boring, noisy, intrusive ads versus info on its website.

Facebook users want to talk to their family or friends, they don’t want to look at ads—much less buy the products in them.

That may be the reason why Facebook is not adding users or advertisers fast enough; its ad revenues dipped recently in the first quarter versus the fourth.  

Also, Facebook could be a momentum trade until the end of the year, after which capital gains taxes rise. An estimated 1.8 billion shares are locked up in private hands. Those shares could get quickly dumped before President Barack Obama raises capital gains taxes in 2013.

Finally, there’s one more thing. Instead of talking about how he wants to fix all of these problems and grow the bottom line, Facebook founder Mark Zuckerberg keeps talking about social values, social missions, and how he would give up stock performance in the short term to meet those goals, whatever they are.

But he could end up owning anywhere from a third to up to two thirds of the company, depending on how this all shakes out.

When you hear a 20-something CEO making noises like that, one with near monopoly voting power, it’s time to worry.

Elizabeth MacDonald joined FOX Business Network (FBN) as stocks editor in September 2007 and is the author of Skirting Heresy: The Life and Times of Margery Kempe (Franciscan Media, June 2014).
Follow Elizabeth MacDonald on Twitter @LizMacDonaldFOX.