>If a service could integrate with telcos and let users pay through them, I'm sure a lot of Indian users would pay for a lot more services than they do right now.

Many of the telecos, however don't want their user's on WhatsApp, they want them to use SMS, I remember Airtel and other's complaining to the government about OTT services, and trying to force the government to introduce a licensing regime for them.

If WhatsApp has to depend on telecos, they for sure will screw it.