In the Management course I did earlier this year there was a section on Marketing. I initially thought that it would be both boring and useless. I was wrong. One of the main focuses was that marketing communications should be consistent when talking to the customer. However, they tried to point out that this consistency is equally important when considering how communications are handed out within the company. Effectively, these communications are the basis how people perceive the company that they work for and should convey the company ethos and culture to the employees - effectively if you send out an email you are marketing. Since people tend to respond strongly to cognitive dissonance the shiny brand image becomes tarnished easily.
I wonder how possible it is to have a positive company culture in a really large organisation that has grown by aquisition - Cisco or IBM, for example.