Well, if $150k in Silicon Valley is "Good", then YES: 100K in Silicon Valley would actually be an "entry level CS salary"
(as scary as that is, being equivalent to the $50-77k we're used to for the same entry level CS job here in Canada)
Consider that a nice 1 bedroom condo in downtown Toronto might go for $400k
The same size of Condo would be priced at $900k in San Mateo.
Salaries for the same job scale with the cost of living (although not a perfect 1:1)