Last week, the Harvard Business Review published a long interview with Howard Schultz. The Starbucks CEO talked about the coffee company's many moves to win back customers and battle against the ill winds of the recession.

As evidence of Starbucks' rebound, Schultz pointed to the biggest of the social networking sites out there. "We're the number one brand on Facebook, he boasted.

Starbucks, in fact, was the first brand to top the 10 million-fan mark. Just to put this in perspective, that's more fans than the entire population of New York City (8.2 million) and all but seven states in the U.S. That's more Facebook fans than its closest rival, Coca-Cola (8.3 million fans) and way more than other large global brands.

McDonald's has 2.5 million fans. Target has 1.43 million, Abercrombie and Fitch 1.37 million, and the trendy teen clothier Forever 21 totals 1.27 million. Among high-end food and food-related brands, Ben and Jerry's has 1.35 million Facebook fans with Whole Foods lagging behind with just 296,152 fans.

The other day, my Facebook page (I have 302 friends) told me that many people who like Barack Obama also like Starbucks. Turns out the President is one of Starbucks few Facebook rivals. He has 10.9 million fans, a few more than Starbucks. But Starbucks still has more fans than Sarah Palin (1.93 million), Mitt Romney (460,832), and Bill Clinton (353,583) combined.

Most pop culture figures don't reach Starbucks' level of fans either. Apart from Facebook leader Michael Jackson (16.6 million) and Lady Gaga (12.9 million), the coffee giant has more online backers than Bruce Springsteen (880,459), Adam Sandler (5.44 million), and even teen idol Justin Bieber (7.88 million).

When it comes to coffee companies, there is no contest. Starbucks' closest competitor (in terms of its number of cafes across the U.S.) Caribou has 154,754 fans. Peet's has 45,497. Not long ago, Time Magazine wondered if the famed Portland, Oregon independent roaster Stumptown might be the next Starbucks. Not on Facebook. It has only 10,780 fans.

BEHIND THE FACEBOOK NUMBERS

From the business side and from the side of studying culture what do all of these numbers mean? Clearly, brands and personalities have turned to Facebook to market their products, enhance their image, and communicate with their customers. But beyond that what does this new form of fandom mean, beyond a sort of crude measure of popularity?

"I signed up because they do promos through Facebook, a high-school friend, who is also a Facebook Starbucks fan, wrote to me in a Facebook message, "I just wanted a free soy latte once in a while.

When you do click on Starbucks' Facebook page, it doesn't go right to the wall to the message board like most individual accounts do, but to a promo page. There you can find out about new drinks, new social responsibility programs, and the many advantages and discounts associated with a Starbucks card.

Facebook is also a place for Starbucks, and other brands, to solidify brand communities. I asked another of my Facebook and graduate school friends why she clicked on the Starbucks fan button. She told me, "I am a genuine fan of Starbucks and don't mind letting folks know that. Back in the 1990s my husband and I were introduced to the coffee by friends and former Seattle residents … We ordered Starbucks coffee by mail for years until they opened the first NYC store near us on the Upper West Side … So I guess we were, I don't know, pioneers? Early adopters?

The wall on Starbucks' Facebook page is an easily accessed and widely used electronic bulletin board for brand shout outs. Posts come in every ten or fifteen seconds. In a matter of minutes, fans from across the globe trumpet their favorite drinks, their favorite stores, and their favorite baristas. Even though there are 16,000 Starbucks around the world, this isn't enough for some.

"We need a Starbucks in Adairsville, GA … Sigh, one fan submitted.

Facebook helps, then, to affirm brand loyalties. And Facebook does serve, as Howard Schultz suggested, as a barometer of Starbucks enduring value and its customers' fidelity. So do the numbers. Last week, Starbucks announced a 9-percent quarterly jump in sales and 6-percent hike in store traffic. But these numbers pale in comparison to the company's soaring fan count on Facebook.

So the question is how deep is that Facebook commitment? What does it mean to click a fan button and how valuable are "fans to brands?

Perhaps my friend who called herself an "early adopter is typical of this new form of brand loyalty. "I signed up to be a ‘fan' of Starbucks on Facebook, she explained, "back when I first started using the networking site. I was pretty enthusiastic and perhaps a tad indiscriminate back then.

In other words, Facebook fan numbers surely serve as a rough indicator of popularity, but this is still only a "weak commitment. Just ask Starbucks' closest Facebook competitor, Barack Obama. He has lots of fans, but that hasn't stopped his approval rating from falling.

Bryant Simon is a professor of American history and culture at Temple University and the author of "Everything but the Coffee: Learning about America from Starbucks.