The current issue of FORTUNE (March 2) has a smiling Mark Zuckerberg, Facebook's 24-year-old founder, on the cover. The business magazine obviously got a photo of Zuckerberg in a tie (a first) and with a smile on his face before he read the cover story.But even though the Time, Inc book thought it was pimping Mark with a glossy full-page picture and mostly fawning piece, writer Jessi Hempel, completely blew it by writing:But attempts to sell traditional online ads on Facebook and other social-networking sites have failed miserably: Banner ads can sell for as little as 15 cents per 1,000 clicks (compared with, say, $8 per 1,000 clicks for an ad on a targeted news portal such as Yahoo Auto) because marketers know that members ignore them.Some readers of this blog may remember when Jack Webb used to say in Dragnet, "Just the facts, 'mam" - something that FORTUNE&#8217;s Jessi Hempel and Assistant Managing Editor Stephanie Mehta should have remembered. Any one who knows even the slighted about online advertising knows that "15 cents per 1,000 clicks" had to be written by a complete ignoramus. Jessi meant to write 15 cents CPM (cost per thousand). CPM is nothing like the performance-based metric cost-per-click, which Google uses to price keywords in its AdWords system. If Google charged 15 cents for a 1,000 clicks its stock price would be as low as Yahoo&#8217;s (around $5.00) and its revenue would be one-one thousanth of what it is.And to write in a magazine that purports to be credible that "attempts to sell traditional online ads on Facebook and other social-networking sites have failed miserably" flies in the face of the facts. The two leading social-networking sites will sell over $1 billion in advertising this year. MySpace is expected to do over $750 million in ad revenue in 2009 and Facebook about $250 million. Some failure. And I'm sure Zuckerberg was pleased to read that "members ignore" ads on his precious site (which is untrue to the tune of $250 million).The assault on credibility is compounded by Editor Andy Serwer in his hyped "Editor's Desk" column in which he praises Hempel's and Mehta's efforts for the cover story. (By the way, on the "Editor's Desk" page there is a picture of Hempel and Mehta with the decidedly un-PC caption "Poster Girls" - honestly. Even an old codger like I am couldn't make this up). Here's what Serwer gushes:&#8230;Stephanie "Telephony" Mehta, who now heads our tech coverage. Stephanie, who covered telcom for years here and at the Wall Street Journal, recently started up our-must read Tech Daily at fortune.com. And like Jessi (who just posted that she is "triple-checking facts"), Stephanie is a serious Facebooker.If Jessi is "triple-checking" facts and still doesn't know the difference between a CPM and a CPC (cost-per-click) and that advertising on social networks is improving steadily because advertisers, even some top brands, cannot resist the humongous traffic on social networks (Facebook just passed 175 million users), then the magazine has no future.FORTUNE used to have superb, expert reporters such as Carol Loomis who could tell if Jack Welsh was giving it to her straight (and Jack knew it) and who would deck Andy Serwer if he called her a "poster girl." Carol could read and interpret a balance sheet as well as any CFO and used to do important investigative pieces. Jessi Hempel wrote an inaccurate, personality puff piece that should have been in People magazine, and you can bet Carol is sad about what has happened to a once-very-good magazine.I'm not renewing my subscription to FORTUNE (I think I've been getting it out of habit) and I never go to its website, which is ugly, out of date, virtually unnavigable and is found at www.cnn.money.com. Well of course, why didn't I think of that?FORTUNE is no friend to Mark Zuckerberg because the writer and editors don't understand his business, and the magazine is no friend of mine anymore because the writers and editors don't understand his business -- not a good thing for a business magazine.