Pros
Most of the people I worked with were quite competent and hard working. I generally had a pretty high regard for the engineers I worked with. The atmosphere is very cooperative - there is an emphasis on respect for others.
Cons
Most of the people I worked with had been working at Lucent (AT&T) for over 15 years. Many had been there for over 20. It meant that the culture was fairly insular. Some engineering ideas and methods that were fairly widely used outside of the company were not used within. Linux was generally not known or used. Telnet was commonly used instead of SSH. General network security methods were not implemented. Test automation was quite advanced in some areas but was often non-existent in others. Quite a bit of the equipment we were using was antiquated. Most had been purchased in the 1990s or before when times were good - there was generally very little money for new equipment. I left just as the merger with Alcatel happened. Before that merger I got the feeling that I was working for a dying company. Since no hiring was going on and the work force was shrinking, no one was being promoted - everyone seemed to be waiting for the big layoff. I dont have many details of what happened after the merger - but they are closing down Whippany where I worked.