It's hard to imagine that a tech company would screen candidates based on area codes these days. I've been living in Seattle for over five years and still have a 415 (San Francisco) area code. I think people tend not to change their phone numbers when moving anymore.

That being said, I'm graduating soon with a PhD in bioinformatics, have an MS in computer science, and I'm not getting any interviews with large tech companies in the area. Maybe I do need a local phone number...