Pros
good for starting a career for software engineers. work for 2 to 3 years you'll learn a lot and after that you do well if you are a superstar category. If you like to write software which sits very close to the hardware then this is a great place for you. It is also great place if you want to work in research (RF, modem, wireless) as qc puts $1billion+ in R&D every year.
Cons
In software groups, moving up on the ladder is through curve fitting like min 3+ years in title unless you are a super star. work-life balance is not a focus at lower titles. San diego is not a great place for software jobs so your best buddies from past years may not be around to hangout with you. If you don't care much for those friends and fully driven by work then Qualcomm is the place for you.