Even if i loved working for Cisco, i can now see actually many drawbacks that made me think i was lucky to leave...
The main one being the lack of career advancement opportunities. Because Cisco grew very fast during the bubble, now all the senior/management positions are currently overfilled, from middle manager to CEO. Additionally, internal moves are difficult, and they are mostly available only between same areas. I feel there is a solid wall between departments (almost impossible to escape from engineering to, say, marketing, finance, operations).
Another bad point is the lack of recognition of your hard work, often barely $500 bonus paycheck that doesn't even pay for the extra work hours (which are anyways rather up to you). But because of all that, Cisco is NOT a fast-paced workplace.
Yet another bad thing, at least on my experience, is the bad middle management. During my engineering experience, managers were great engineers who were promoted at some point. However, good engineering skills goes frequently with lack of management skills, and i saw that too frequently. They were often poor on managing efficiently, mentoring junior members, dealing with conflicts, etc... and played too frequently dirty politics. Of course, they don't necessarily receive formal management training to alleviate that...
Finally, size and bureaucracy associated with it can be frustrating at some times, or can be good at others (provides kind of anonymity).
