Assuming Celtic wanted to appoint Owen Coyle (and I've spoken to fans who will swear blind they didn't - conspiracy, media agenda, etc etc ) they are now on their third choice in Tony Mowbray, who I think will end up going there.
Now assuming Strachan didn't quit on the spur of the moment (I'm led to believe he was set to quit last summer but didn't in the wake of Tommy Burns dying) it would seem Celtic have been slow out of the blocks, or haven't done their homework on potential candidates.