Mumbai is the place to be for a lot of people, but maybe not for core tech and programmers. We don't have a very strong programming community here (though we are trying to build one). We don't have as many tech events and communities as Bangalore. Mumbai has quite a few startups, but again, there are far more in Bangalore. And the worst thing is Mumbai is quite a bit more expensive to live. The rents are very high, probably double of the Bangalore rates. And you don't really get higher salaries to balance this out.

This has been my experience with Mumbai. You may be happy here, depending on what job you get here, and what circle of geeks and friends you find around here. In general, it is a much more happening place than Bangalore.

Edit: Obviously, both of these options are far better than Jaipur. Bangalore, Mumbai and Delhi are the places to be for working in tech. You can probably add Pune, Chennai and maybe Hyderabad to that list, but that's it.