I can't speak for the asian countries since I've never been there, but according to http://www.internetworldstats.com/asia/th.htm, the situation in countries like Thailand is way better than what you describe (I didn't take the time to check the other countries).
You'll find poor people with really bad jobs, that's true, but it's not the norm as most of the foreigners seem to think.

To speak from my local experience: "Broadband" Internet Penetration (broadband by local standards is 128Kbps+) in Medellin was near 18% in 2008 (http://medellin.gov.co), not great but definitely nowhere near your numbers. The situation in Argentina, Brazil and Mexico is way better, so I don't know what you use to create your estimates.

Have you considered serving relevant ads to your users in those regions?
The ads I see for all networks (including AdSense) in Latin America are: "Find sexy colombians", "Get a degree at the University of Phoenix, Arizona" and "Green Card Lottery, click here!". Maybe that has something to do with the companies not generating enough revenue.

I'd love to know which third world countries you've visited, saying that 99.9% of the population connects through internet cafes just shows some ignorance from your part. Maybe we have to divide third world between "really undeveloped countries" (Western Africa) and "undeveloped countries" (Latin America, Middle East).

Federico, a guy from Colombia (LA) with a standard 3Mb connection who doesn't work in a sweatshop making Nike shoes.

Javascript is also a full fledged programming language, whatever that means, you can run it inside a JVM (Mozilla Rhino) or using any other engine like Spidermonkey, which means you can pretty much do the same things you can do in Java.

Funny, eh? :)