I have lived in San Diego about 24 years all total, and only moved out of there again a year ago.
I like the climate ok, and there is plenty of stuff to do, and all my family lives there. It's a great place to be a single college guy, and will probably be a great place to retire.
I don't feel it's a good place to raise a family. The two income family is pretty popular nationwide, but it's assumed in San Diego, and there is a strong materialistic current to always have the fanciest house and expensive cars, etc. This means that areas with decent schools have really inflated house prices, and the areas where a working family can reasonably afford have schools which would be an embarrassment in 3rd world countries - and private schools are impacted and priced to match.
So if you're not planning to have kids, or they're already grown - SD is a nice place to live provided you have the income to afford it. If you're wanting to start a family, either have a really good income(seriously, top 5%), or consider other areas.
~edit~ On the topic of traffic: SD is pretty light. Yes, during the morning/evening rush the 805/5 merge, and the 8 between 163 and 15 can be ugly, but I worked in Sorrento Valley and lived in La Mesa and even in the worst traffic that was only an hour for ~25 mile commute, and most days around 30 min.