Hi, dchep,
Absence of the duration label on iMovie clips has been reported by many on this forum following the recent updates. Apple will need to address it. Nothing you can do about it.
Some posters have observed that you can get a duration reading by pressing and holding your cursor at the beginning edge or ending edge of a clip.
Also, you can select the clip and click on the information icon (the circle with and "i" in it) located in the tool bar at the upper right of your screen. A duration box displaying the clip's duration will appear in the duration box below and to the right of the icon.
-- Rich