hey all... i gave my hen some store bought eggs that are 'due' on the 13th.  I thought I'd check in and see how everyone is doing.  Congrats to those who have little ones already!  That gives me hope.  I tried to candle the eggs tonight and saw big air pockets in the ends... I was totally bummed, but then read somewhere online that is normal.  I didn't see a lot of movement, but didn't dare hold them out too long either.  I gave her 7 eggs, if she gets even a couple babies, I'll be happy for her.  
Good wishes for everyone who's still waiting!