[quote=bearishgurl]AN, I maintain that the avg salary in SF is 40% higher that the exact same position pays in SD County.[/quote]
Here are some data to dispute your claim:
S/W Engineer 1 – 14% higher:
Palo Alto – $71k http://swz.salary.com/SalaryWizard/Software-Developer-I-Salary-Details-Palo-Alto-CA.aspx
SD – $62k http://swz.salary.com/SalaryWizard/Software-Engineer-I-Salary-Details-92121-San-Diego-CA.aspx

S/W Engineer 3 – 26% higher:
Palo Alto – $116k http://swz.salary.com/SalaryWizard/Software-Developer-III-Salary-Details-Palo-Alto-CA.aspx
SD – $92k http://swz.salary.com/SalaryWizard/Software-Engineer-III-Salary-Details-92121-San-Diego-CA.aspx

S/W Engineer 5 – 16% higher:
Palo Alto – $143k http://swz.salary.com/SalaryWizard/Software-Engineer-V-Salary-Details-Palo-Alto-CA.aspx
SD – $123k http://swz.salary.com/SalaryWizard/Software-Engineer-V-Salary-Details-92121-San-Diego-CA.aspx

RN (Staff Nurse) – 16% higher:
Palo Alto – $81k http://swz.salary.com/SalaryWizard/registered-nurse-Salary-Details-Palo-Alto-CA.aspx
SD – $70k http://swz.salary.com/SalaryWizard/registered-nurse-Salary-Details-92121-San-Diego-CA.aspx

MD (Family Practice) – 16% higher:
Palo Alto – $216k http://swz.salary.com/SalaryWizard/Physician-Family-Practice-Salary-Details-Palo-Alto-CA.aspx
SD – $186k http://swz.salary.com/SalaryWizard/Physician-Family-Practice-Salary-Details-92121-San-Diego-CA.aspx

I think that enough data to prove my point about salary, no? My personal experience fall perfectly inline with these averages. About 15-25% difference between different companies.