Our family heard it in Ross Twp. It was loud enough to rattle the windows here. Sounded like one loud thundercrack, but given people have said they heard it from Moon to Oakmont to Greensburg to Bethel, it looks like something higher up in the atmosphere is more likely than something on the ground.
In other news - Thursday seems to be flirting up and down on WUnderground with totals. Temps look right, at least.