I surely can't speak for him, but I can offer my own experiences. I was born in Chicago, but moved to Puerto Rico when I was a kid and lived there for 20 years. Puerto Rico is much, much cheaper than anywhere in the United States (My rent for the two-bedroom apartment I was living in was $250 per month). But after being stuck in a meaningless PHP gig (where I was more of the company sysadmin than a developer) and having a difficult time getting a programming job, I started looking to the U.S. for a better opportunity.

I landed a job in New York City, where I'm currently living at. The city is awesome and my job is fun. But in reality, the Bay Area was my first choice, and it's still dream of mine to be able to land a job over there. I'm in the process of getting more information to further my skills so I can begin actively searching for work over there.

I was doing well in Puerto Rico (earning more money than most people I knew, living close to beach with constantly great weather, all my friends and family living there, etc.) and I'm certainly doing well in New York City. But if I had the chance to move to San Francisco, I wouldn't think twice about it. Maybe I'm wrong, but the Bay Area is kind of like the Mecca for developers and aspiring entrepreneurs like myself.

Like I said, I certainly can't speak for mannicken. I'm sure he has his own reasons, perhaps even similar to my own reasons. But if he's really willing to do it, that should be reason enough, regardless of where he is now.