NEW YORK (Business 2.0) - Monday's Viacom purchase of Neopets, the hugely popular children's Web site that's a natural fit with the Nickelodeon brand and a natural digital platform for Nickelodeon's properties, is exactly the kind of "targeted acquisition" Viacom chairman Sumner Redstone promised in a press release last week when the company announced its plan to split in two.

The purchase may also confirm the conventional wisdom that Redstone pushed for the split just so he could swap out the boring bits and pursue his recent passion for buying digital media businesses of all shapes and sizes.

He'll have to, the thinking goes. After all, how else can the new Viacom (Research) -- which was explicitly designed to be a growth stock -- maintain the torrid pace set by the company's cable networks over the past few years, when both revenue and operating profit have grown about 20 percent annually?

Sooner or later the company will burn through that propellant, and management will need to be ready with new businesses to supply thrust. New businesses that look like Neopets, which hits three sweet spots: children, the Web, and wireless opportunities.

But here's a thought: What if Viacom already has every customer it needs for the next five, 10, or even 20 years? What if the "organic expansion" Redstone also promised doesn't depend on inventing new brands to strip-mine both the gay male demographic (that would be Logo, the cable channel launching at the end of this month) and the very, very straight one (Spike TV)?

I'm willing to hazard a guess that Viacom's fortunes a decade from now hinge on the loyalty of 12-year-old girls watching MTV right this second in Jakarta, Indonesia; Johannesburg, South Africa; São Paulo, Brazil; and Shanghai, China. Viacom's most important task between now and then is figuring out how to make more money from them.

MTV International is thought of as a huge branding success for Viacom -- when it's thought of at all. In fact, MTV is now available in 44 regional flavors in 164 countries, ranging from MTV Mandarin to MTV Base, which launched in Africa this year and planted the channel's flag on its sixth continent. MTV reaches 415 million households across the globe, and at least a billion budding young consumers know the brand.

But its long-term importance to Viacom going forward -- and to the new company's CEO-in-waiting, longtime MTV chief Tom Freston -- has gone almost entirely unmentioned since Viacom's board began ruminating the split back in March.

It hasn't been lost on Viacom execs, though. The same day that news of a potential split broke, MTV International's longtime president, Bill Roedy, was formally tasked with jump-starting the channel's online efforts abroad. The next afternoon I spoke with Roedy about the next phase of his job, which is to begin converting brand awareness into cash.

"On the one hand, eight out of every 10 viewers live outside the U.S.," he told me. "But on the other hand, we're very early in most of these countries -- we're nowhere near making $8 out of every $10 in revenues and Ebitda there. Our growth is still very much ahead of us."

Especially when you consider that less than a sixth of Viacom's revenue came from abroad last year, and only a sixth of that fraction came from South America and Asia, where four out of those 10 MTV viewers reside.

It won't be easy, and even in countries where the local MTV is already a decade old, like India or China, the channel has been able to grow only as fast as the infrastructure.

MTV India's annual revenue, for example, is in the neighborhood of just $25 million. And while an aggressive digital strategy in Japan and Korea sounds great in theory, so far there's little to show for it.

But Viacom's great stroke of genius under Roedy was to aggressively decentralize the brand. Everything from daily programming to the profit and loss statement is the responsibility of executives on the ground in each country, who have in turn molded the brand to please their very discerning audiences -- MTV India airs Bollywood spectacles, while MTV Indonesia leads viewers in prayer five times a day.

"We came out of the gate intuitively thinking that you have to be local to connect with the audience," Roedy says. "That it wasn't only about the language and the music, but sensibility...even though the brand can be the same everywhere."

And yet it's not. MTV's strength is that it can be anything it needs to be, as conservative or kooky as local tastes demand. It's ubiquitous, beloved, and unlikely to be unseated in-house by any brand during the next decade, no matter what Sumner Redstone buys.

So for all his talk of new opportunities, new platforms, and a new-and-improved stock price, Viacom's fortunes still depend on the kids -- wherever they are -- wanting their MTV.

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