With Akonadi most operations are running behind the scenes, carried out by background helper processes called Akonadi Agents.
While we do have respective progress monitoring in KMail2, users will eventually take advantage of fact that they are no longer tied to specific applications. At which point they might want to be able to check on the status of these background processes without launching some front end applications.
Back in April, during one of our development sprints, I've created a Plasma DataEngine which provides information about running Akonadi agents.
I was kind of hoping that somebody with actual widget skills would be curious enough to try some Plasma widgets on top of it, alas this didn't happen.
The code for it more or less looks like this:
It shows the widget running in plasmoidviewer side by side with Akonadiconsole to demonstrate that the data engine really exposes the same data.
Finally I synchronize all collections of the IMAP resource, showing status and progres reporting.