Pros
Lots of highly-competent and experienced engineers, cutting-edge ASIC technology, acceptable benefits and compensation. Senior management (VP and above) on the technical side really know their stuff. If you can cut through the politics and some big egos to find your niche, you can really do quite well.
Cons
Inter-office politics really kill employee enthusiasm. Two sites in particular are constantly fighting for supremacy (including promotions, technical responsibilities, and general recognition), and the other sites are simply along for the ride. Compensation is merely acceptable, not great. Recent trend is to add managers, rather than engineers. Management below VP level on technical side is really hit or miss. Engineers with too-specific a skill set can get stuck in a rut.