The biggest problem in Philadelphia is that its a really cost effective city to live in, so you aren't going to get the sky high paying tech jobs that you find in other cities, because there is a big pool of workers from the larger employers that are always around for modest wage increases. That depresses wages, and makes really talented engineers look at moving towards NYC or DC where they can get a _much_ better paying job. Specifically NYC where you can still live in the suburbs and make NYC level wages by only moving a half hour north of Philadelphia.