I spent part of a summer working in Menlo Park, after having lived in Chicago and New York. As far as I can tell, its a mixture of the worst parts of New York City and suburban DC (where I grew up). A highway is the major reference point. Nice restaurants are in strip malls. Its way more suburb-y than Westchester or Greenwich, and more disconnected from the central city. It is, however, very clean by virtue of religious power washing.

What's most disturbing is the monoculture. I got a haircut and the hairdresser was talking about startups. Also, in New York you're likely to see kids in the same visual frame as bankers. In Silicon Valley, families seem segregated from the working age people in the characteristically suburban way.