This. Now, I don't actually understand statistics at all, so please correct me if I'm missing something, but as a European I find this poll pretty telling, and a good indication of what to expect if I'd consider moving to the Valley.
Clearly, at least the maker of the poll seems to assume that I can expect to earn at least $80k-ish. I earn a bit over half that now. This is a very big difference.
Additionally, given that most people in this poll earn well over $100k, and I'm a pretty experienced programmer, this poll teaches me that asking for, say $120k, at an SV company, isn't an odd request. People won't frown or laugh at me. They might not want to pay me that, and just as well I might be undercharging, but it's not out of the question.
Can I draw these conclusions? If not, why not?