MICHAEL LIEDTKESAN FRANCISCO (AP) â¿¿ EDITOR'S NOTE â¿¿ Facebook begins selling stock to the public Friday in the most talked-about market debut in years. Two Associated Press business writers are debating whether the stock is a smart buy. I doubted Mark Zuckerberg when I met him more than five years ago, shortly after he rebuffed several chances to sell Facebook for what was a fortune even then. He seemed confident to the point of being cocky about his ability to turn what started as an online hangout for college students into a digital commune for the entire world. Facebook had about 20 million users at the time. While listening to Zuckerberg pontificate on Facebook's potential to become a more important communication channel than long-established media outlets, I wondered whether this then-22-year-old kid was deluded. Had he screwed up by not accepting one of those buyout bids ranging from $800 million to $1.5 billion that were dangled before him during 2005 and 2006? Clearly not. Now I think investors who don't buy some Facebook stock within the next month will regret it in five years, when the Internet's largest social network will have more users than the population of China. As it is, Facebook has more than 900 million users and will have an initial market value of $104 billion â¿¿ more than twice as much as the combined value of two former suitors, Yahoo and Viacom. Zuckerberg, who turned 28 on Monday, pulled off the initial public offering just eight years after starting Facebook in his Harvard dorm room. Just imagine what he might be able to accomplish by the time he turns 35, now that Facebook has raised $6.8 billion in its IPO. But don't wait too long to find out. At some point in the next few days or weeks, seize on the IPO as a rare opportunity to prosper from the ingenuity of a headstrong visionary in the mold of Apple's Steve Jobs, Microsoft's Bill Gates and Google's Larry Page and Sergey Brin.