I've heard that Irvine has much more money than Davis, though I have not independently verified that. Don't let Riverside's low ranking (#64) fool you -- they are a good school, almost comparable to Davis. Merced is a joke, they don't even have a physics department per se! UCLA is very competitive. So basically, in terms of reputation.
Santa Barbara / Berkeley
Which leaves out San Diego and Santa Cruz, not sure how they fit into it.
First, it is definitely not the worst of the UC's. UC Merced is worse. Second, it very much depends on your field of interest. Their experimental high energy is very strong, their high energy theory is pretty good, their condensed matter has a lot of people and is quite good. Third, being from a top ten school will help in getting faculty jobs, but below that it doesn't really matter. Your advisor and your work is more important.
Dragging up a year old thread, but how would this kind of perception of UCM affect chance of landing a job (faculty position)? It doesn't seem all that good if even professors have low opinions of a fairly new program.
got the admissionprof's quote from: viewtopic.php?f=21&t=2276&p=22321