I am perhaps one full nerd who does not check his hotmail account everyday. We have them on our blackberries, my wife checks hers and get a lot of mail, but I sometimes go days without looking.
This is key to make for the future of KM. Email should become an unusual form of communication eclipsed by the new communication media like the fax has been eclipsed.
Email has many problems and few benefits. For providing a single comms tool for your works you end up losing a single version of the truth, that increases the amount of written documents you are liable for without letting you know it.