There are some things that you don't want to bet against -- such as gravity or increasingly bizarre hairstyles on Britney Spears. Another is the stunning growth of wireless services in developing nations. With its third-quarter earnings, America Movil (NYSE:AMX) showed once again that the spring of near-30% growth in wireless services in Latin America is still flowing.

The company that, along with Telmex (NYSE:TMX) and other interests, helped vault billionaire Carlos Slim Helu to the title of richest person in the world, reported revenue growth of 29.8% to $7.2 billion for the quarter. Earnings before interest, taxes, depreciation, and amortization (EBITDA) rose 44.6%, but net earnings of $1.03 billion were actually 2% lower than last year, so obviously there's something missing in the middle.

The big bite out of the bottom line came from a few areas -- one was increased depreciation expense and another was a bigger tax bite. The higher depreciation charges stem from removing equipment and services based on an old technical standard, called TDMA, in some countries. Other operators, such as AT&T (NYSE:T) in the U.S., have moved to retire these networks and move users to newer service platforms.

Chile was the only market where America Movil had a net reduction in wireless subscribers for the quarter, characterizing the loss as a "cleansing" of the base there. But the company is generally holding its own against main rival Telefonica (NYSE:TEF), growing its wireless subscriber base 4.5% in the quarter by adding 6.2 million new subscribers. With a total of 143.4 million wireless subscribers across more than a dozen countries, America Movil shares the scale of global behemoths China Mobile (NYSE:CHL) and Vodafone (NYSE:VOD).

America Movil's stock took a dip after the earnings release, but shares still sit nearly 50% higher than where they started in 2007. The lighter-than-expected earnings and continued rise in the stock will make America Movil look more expensive to investors. But compared with its peers, I still find this giant company a cheaper way to tap the booming growth of wireless services in emerging markets.

More Foolish musings:

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.