What surveys usually lack are questions that link the communications you manage to the effect they have on employee behaviors, which result in improvements in the bottom line.
Why you need to make friends with others who measure results: Communication measurements can be even more powerful when compared against measures of operational outcomes communications is affecting.
The ultimate measure of customer communication is sales. The trick is to find ways of tracking your communications against sales in a way that eliminates the effect of other factors.
Perceptions generally need to be quantified by a survey methodology administered to your key audiences. Behaviors are better measured by tracking outcomes.