Of course, Cambridge and many areas of Boston proper are quite expensive (as are some of the tonier suburbs like Concord).
Silicon Valley is a bit unusual in that you can't really escape from high prices, in spite of being suburban sprawl, because of the geographical constraints.
But the most job growth in the country requires that people move there (here) and they require houses when they arrive. With that surprising increase in demand, I expect I could get $250,000 for my house now, which is a staggering increase in a fairly short period of time.
On the other hand, if you're coming from a place where houses are selling for $1,200,000 (the 4 * $300,000 suggested above), then maybe you still see $250,000 as being affordable. We certainly have jobs. Every place of business in the area seems to be hiring.