I would love to see some sort of cost-of-living analysis that didn't just look at average costs of housing and food but also incorporated some mental measure of "being well-off" that used the area's Gini coefficient [0]. I say this because I have lived frugally in Santa Monica, CA and I have lived frugally in Atlanta, GA at approximately the same standard of living but being surrounded by conspicuous outliers definitely made me feel much poorer in Santa Monica. See [1] for academic discussion.
[0] - http://en.wikipedia.org/wiki/Gini_coefficient [1] - http://www.ncbi.nlm.nih.gov/pubmed/20503742
This analysis is not hard to do for a specific job. If you're looking at a job at a 10-person startup in LA, go to AngelList and look up job postings at 5-10 other LA startups that are a similar size. You'll get a great sense of what a typical offer looks like, and then you can compare that to your own offer.
But even adjusting for the cost of living, I'm glad I see figures like this because it shows how ridiculous some offers are. I got an invitation to apply in Los Angeles last week for webdev, with the bottom set at $40k and the max set at $70k