This bug is, I guess, incidental in the great scheme of things, but I thought I would post as I have now stumbled across it on a couple of occasions.
When I display the information panel in a resource (as per below),

And then select another tab (backgrounding the information panel),

The information panel then disappears (as per below),

I appreciate that this is a very minor issue, but it consistently repeats regardless of the resource. It is easily remedied, click 'done' and then reselect the information panel.
I am working on 4.5b SR-3 on a 2011 MBA (as per footer).