I grew up in Atlanta but have lived in Chicago, Washington state, Florida and Tokyo, Japan. I now live in Mountain View, California in the heart of the valley.
Atlanta is a great place to live, raise a family and has its own unique tech/geek/startup culture. It's hard to compare the valley to Atlanta - but that's true with any other location on the planet. Silicon Valley is unique and difficult to replicate.
These types of "centers" happen because of aggregation of people and resources. Nashville has an aggregation that supports country music, Atlanta has hip-hop, LA has Hollywood, D.C. has politics and NYC still is the financial capital of the world. Silicon Valley is just the technology capital of the world. With any rule, you have exceptions - plenty of great technology companies come out of Vancouver, Seattle, Portland and Denver (just to name a few).
What Atlanta and all other places should focus on isn't how to replicate the valley - but instead, how to create their own unique place which highlights and rewards their own achievements and strengths. It will take a lot of constituents to make that happen - entrepreneurs, investors, law makers and educators.
One stark contrast that might be worth exploring is the difference between the Valley and other locations is reinvestment through the social contract. In the Valley, there is a very strong sense of a social contract from entrepreneurs to entrepreneurs (and investors to entrepreneurs). I feel a much stronger sense of success which breeds more success (or help, resources, guidance and mentorship). In fact, anecdotally, it seems like way more entrepreneurs "who make it big" in the valley, attempt to repeat - either directly in their own subsequent startups or minimally through very active advising and investment in younger upstarts. I would contrast that to Atlanta where I believe that's more of the exception than the norm. (Plenty of people have such as John Imlay, Mitch Free, Alan Graber, Tom Noonon, just to name a few). My own personal assessment is that it might be because there are (a) fewer very large exits in Atlanta, (b) it's easier to retire with less money in Atlanta and (c) there's no peer pressure to do it again.
Recently, however, I'm very encouraged by all of the entrepreneurs that have decided to take things into their own hands. Atlanta knows who they are (Lance Weatherby, Scott Burkett, Sanjay Parekh and all the guys at Shotput Ventures like David Cummings and Mitch Free). I've long said it's the entrepreneurs that will "save Atlanta" -- if there is such as thing that people believe is necessary.
I'm very much rooting for Atlanta. Not to become yet-another-failed-silicon-valley replication attempt. Wow, gives a f* about that. I'm rooting for Atlanta to become it's own identity: something more powerful, more creative, more sustainable and more unique. Something that people say: "you can only do that in Atlanta".