Nope, no light on top of my head unit - white or red. To see if it is working (or for that matter, if the battery has given out), I have to stick my hand in front of the head unit and see if it is lit up.
I shoulda got the Xtra - the extra cost for the indicator light and the longer-life battery is worth the extra cost.
Maybe I'll retire this one to my summer bike, and get the Xtra for the Winter commuter...