Pros
In terms of benefits Qualcomm is excellent. Free gym, good 401k match, good pay, decent bonuses and stock options, excellent health care (free), many employee programs, lots of tech training, nice campus, onsite cafeterias - you name it.
Cons
The company is a dinosaur. The management structure is deep with many redundant levels and political power structures. Decisions are not made for technical reasons but rather to benefit your Director or VP. There are periodic layoffs that tend to hit the lowest performers first, but they also lay off those who do not "fit in" (ie. anyone who actually has good ideas and is somewhat vocal.) Job performance is increasingly about perception rather than results. Career advancement varies great between departments. If you are lucky enough to have a benevolent manager you'll get promoted every few years, if you have a bully you'll be forever stuck in the same role (ie. 10 years or more) since you're not deemed worthy despite all your excellent reviews. Qualcomm could easily reduce headcount by 75% and still keep their core businesses: Modem and MSM. They are and old, slow, flabby company that is only focused on cost reduction rather than innovation.