And a Gini coefficient (.531 as of 2011) between Guatemala (.530) and Colombia (.535). Italy and Spain are at .319 and .359 respectively. The US as a whole is .475.
It's an inequality coefficient, not any kind of measure of how "nice" a country is for someone living there.
Countries with a high Gini, tend to segregate more heavily than those who don't, which for the typical 'rich' software developer means that they'll live in a trendy area and know to avoid the 'ghetto'.
For example, Miami has a high gini at ~0.6 to 0.7 which gives you the palaces overlooking shacks effect of Miami Beach.
High gini also correlates with extreme economic growth, where the benefits fall onto a small group (e.g. software developers), and a reversion to the mean hasn't yet taken place.
County statistics are misleading here. Santa Clara County is a big place (almost the size of Long Island) with lots of municipalities. New York County is just 1 of 5 counties that encompass New York City!
If you look at Brooklyn (Kings County), the number is 0.499, Queens County the number is 0.433.