While looking for owls in Tryon Creek State Park on 2 February 2014, I came across a male Pileated Woodpecker in the early stages of excavating a cavity on the w. side of a dead tree approximately 10 meters above the ground. I am now happy to report that today I found both expecting-parents sharing incubation duties within the same nest cavity. Given incubation lasts about 18 days and the typical (3.83) offspring begin perching at the entrance watching for the parents 20 days after hatching - my guesstimate is that we can expect lively family shows to begin there sometime during the week of May 12th. The time between switching-out incubation duties on this day was exactly 60 minutes. Seven Images:

Male watching the female depart right after relieving her of her duties. 

The female arrived back at the nest exactly 60 minutes later producing short low-pitched calls on approach - the male could be heard tapping/drumming from within the cavity before departing - you will notice she wasn't the slightest bit concerned about his departure :)