How Does a K-Log Work for Notification?

Curiouser and curiouser! has pulled together a variety of sources on the topic of using k-logs to avoid choking project managers’ email queues:

Reuters:  Managers drowning in e-mail.

A huge volume of business e-mails is generated from workers reporting progress to project managers, Nickerson said. <<<  There is an answer to this:  post it to your K-Log.  K-Logs are more passive and user friendly than e-mail. 
[John Robb’s Radio Weblog]
[Jim McGee: Blogging]
[Ron Lusk: Ron’s K-Logs]

I shall be leveraging this argument quite heavily I think.
Savvy people already realise that email is the rope they’ve tied around their neck.  I think they are just afraid to do anything different in case they pull the handle for the trapdoor.

Hopefully the k-log message will resonate with these people in a good way.

What I don’t get is why a k-log would be better than some sort of toggle or checkbox in a database that the KM could look at? I’m not sure how pure business k-logs look, but woul the project manager have to search for “I finished debugging the widget” to be sure she had your seen your update? How passive is passive?