Hi Drew,
There is currently a feature request for a MTC display.
http://tracker.figure53.com/qlab/ticket/398. I am not actually 100% sure but I don't think that you get an indication of MTC input in Qlab at all. You can get an indication of it coming in using Snoize's MIDI monitor, but the monitor only sees the quarter frame messsages, and will not display a readable clock for you.
As an alternative you can get an external MTC display of some description.
Have a look at
http://shop.punchlight.com/product_info.php?cPath=132&products_id=52173032
http://www.bonsaidrive.com/mif3.htmlBoth of which will display incoming MTC for you, unfortunately they are not particularly cheap!
You could also consider using a DAW and syncing to the external MTC and using the clock on that as a visual reference.
Regards,
Fergus