To address a few of the concerns brought up elsewhere in this thread:
Yes, you'll probably end up working as a contractor. Personally, that's my preferred work style so I see it as an advantage. For Europeans I could see how it could be considered a disadvantage.
The big upside is that US companies are used to paying market rates for developers, whereas EU companies are not. That means realistically you'll be bringing in a significant multiple of a typical EU dev salary, which will more than offset any of the little issues you need to deal with to be self employed over here.
As to timezone concerns and worries about having to compete with $10/hr freelancers, well, it's just never been an issue for me. My work product is the same regardless of where I'm sitting when I do it, so I charge the same rate you'd need to pay for me to do it in the Bay Area. And I work during the day, so if you want to talk we can do it when that's happening for both of us.
Now, I'm sure lots of US companies would be happy to negotiate those things away from you. But if you're good at what you do and they want to hire you, why would you let them?