Indian government announced it's 3G policy for telecom industry. They expect the mobile operates to start the service by December this year. That is if the auction for the spectrum goes as planned and there is no government change in the mean time. This will be a big cash cow for the government which is expecting to earn around 40000 crores. So if something happens to the present government this auction could be the first thing that will be stopped. They need some sort of income to pay all the corrupt politicians for the next government.
If everything goes well by January we can expect the service to start. But expect to pay a premium for the first few months where ever the service is available.
Like 2G, don't expect the 3G service to roll out to small towns at least after 3 to 6 months time.
Also save up because you will need a 3G capable phone to take advantage of this service.
Only most high end phones come with 3G, so save up all your money now. Because you will be paying quite a bit at least in first few months for the 3G service.