Pros
It's a big company. There are a lot of opportunities for lateral movement. But the company doesn't grow like it use to so if you have aspirations to move up into management it's harder then it use to be. On the other hand, most individual contributors don't want to move into management. But if you are looking for a good technology company where the work will not be shipped overseas as much, then Cisco is a good choice.
Cons
The management structure is different from other companies. Cisco believes in a flat structure. The typical 1st level management position doesn't exist. Cisco uses technical leads to perform much of the function that a 1st level manager will perform in most companies. Also because the structure is flat, individual contributors will often go directly to upper management to discuss issues and concerns. It's not only the norm, but in many ways encouraged by upper management. They want the "scope" If you are a manager you'll find yourself doing a lot of the grunt work. Cisco engineers have a habit of not wanting to do plans, documentation, etc. They just want to focus on the engineering tasks. So these kinds of things that are typically first level management issues will fall on you, where the technical lead will usually take most of the "fun" aspects. If you want to go into management when there is an opening isn't very hard, if you've been a good I/C. Most engineers at Cisco do not want to go into management. They would rather remain I/C. And why not, there is a lot of stress in management and compensation for good I/C can be just as high if not higher than management. In this tough economic times, Cisco will periodically want you to review your performers. Usually they are looking for you to let someone on the bottom go. If you cannot stomach the idea of firing someone then Cisco is probably not the company for you.