To quote, River Song "Spoilers".
I’ve made no real secret of the fact that I’m not the biggest fan of Steven Moffat’s time as head writer on Dr Who. I think the quality of the writing has decreased and the focus has become spectacle and viewing figures instead of good characters and well-executed narratives. Plus, his last 3 seasons have included far more complete duds than the Russell T era was ever guilty of and, in my opinion, the vast majority of great episodes come from the first 4.5 series of the rebooted show. However, I was just as excited as the vast majority of the world about last night’s 50th anniversary special and sat in front of my TV praying Moffat would pull it off.