when do you expect to finish your training? if you are a third year med student, then you have at least 8 years until you have to worry about this. it's impossible to know what the market demand for ct surgeons will be then, in particular in a given area. if one group hires 5 new surgeons, the area is saturated. if another group leaves town (or has 4-5 leave), the market is wide open. in a field where a small number of surgeons covers a large population, simple shifts can have huge effects. on the other hand, it's doubtful that there will be a huge shift in either direction in the supply of pediatricians for a market this large. for something like neurosurgery or ct, big market shifts can happen rather quickly, even in a place like la-la-land.
that being said, southern california is a desirable place to live and many will continue to want to live there. this desire to live there has been taken advantage of in the form of lower compensation (same with nyc). if you notice, the big paying jobs are in north dakota and wyoming...
moral of story: figure out what you want to do for a living. then worry about the job market. if you're dedicated to your field, you will get a job and be successful. if your desire to invest 7+ years of post-md training in a field depends upon a given city, consider reevaluating. your spouse may need to live somewhere else, you may run into political turf-wars in that region and need to go elsewhere if you piss-off the big cardiology groups.
if you want to do ct, dive in head first! it's a great field, and the sky is NOT falling... if you first and foremost want to live in so cal, go into plastics or derm...
