Establish metrics on web traffic, usage, and feedback that are cross-platform and easily gathered. (For example, although ForSee results are easily interpreted, they are not "easily gathered" as the survey is pricey.)
Establish guidelines for what websites should track (visitors? views? return visitors? tweets? back links?) etc. and what "good" is in each of those metrics.
Then report on these metrics within departments and *share* these metrics within departments so that they can become actionable lessons learned.