It would be interesting to know how and why e-newsletters are used and how successful the ROI is for Government organisations.
There seems to be stats available on the implementation and use of "Intranets". Obviously the Intranet is a more used tool, but the newsletter can contribute to the companies internal goals. Both of these tools are internal communication tools.
There is a lot of writing that says internal e-newsletters are popular (obviously they are.). There is also a lot of advice on what to include . There doesn't appear to be established stats to verify this...or investigate what types of topics are popular in an organisational internal newsletter.
For some companies a newsletter is an investment in time and staff, I require stats to qualify this investment.
A lot of this stuff would be organisation and newsletter specific, but I thought/hoped a study might have been completed.