I have worked at Cisco Systems since June 2011. The culture is great and the people are great. Also, I really like Cisco's emphasis on customer-driven innovation! The only negatives are the same as most large, bulky companies. Slow decision making and slow to adapt. Also, Cisco has had three or four layoffs in the past decade.
Cisco was overall a good company to work for. Though they were overly eager to use contractors, which meant a lack of benefits, they had a great company culture and an environment of openness and acceptance of all diverse cultures, beliefs, etc. However, the company has the worst physical and digital organization I've ever seen. This could be simply the department I was working with, but document storage and retrieval was very convoluted. Also, communication needs improvement.
Weed out worthless managers with qualified ones. In Cisco, there are managers without any portfolio - nobody reports to them, and directors who do not have even any team to direct. Seriously!