Brin's advice rings true to me. Silicon Valley has changed since Google started. It has become a tough place to bootstrap a company from scratch especially if you are focussed on getting to profitability at an early stage.

Expenses in Silicon Valley are high and show no sign of declining. Even more important it is hard to find qualified staff in SV who are interested in working on start-ups that don't have strong funding. Most companies therefore look for a somewhat lower cost place with qualified engineers and have done this for a while now. At some point you have to ask why not just put the whole company somewhere else.