Indian entrepreneurs and software developers have been attracted to the Silicon Valley for all the usual Californian reasons. The heart of the Valley is a social and economic culture that values imagination, expertise, and energy--Seize the Day!--over history and skin color. No one sits around Palo Alto whining that there isn't enough to do downtown and waiting for someone to do something. There isn't a lot to do in downtown Palo Alto (I grew up there, my family still lives there, I go back at least once a year), but everyone and his mother is brainstorming new ideas, raising money, hiring friends, and launching new businesses. Many of them fail. Even most of them. But they get up and start again.And so it comes to pass that the Indian population in the Pittsburgh region has nearly doubled over the last 10 years.
Lesson: Pittsburgh will have a hard time attracting more of these sorts of immigrants without doing more to change its historical resistance to social and economic entrepreneurship.
Chris B., as usual, has much more detail, including pointers to material from a month ago that I missed because I was out of town.