The climactic moments brought out the fanboy in me, I'll leave it at that.
I was originally disappointed to hear that Christopher Eccleston wasn't going to have a larger role alongside Matt Smith and David Tennant, but his absence makes sense with the plot. Being the darkest of the modern Doctors, he seemed the most traumatized by the actions of his former self the so-called War Doctor, played exceptionally well by John Hurt.
This was a nice capper to the current run of Doctor Who, and I look forward to the next special which will officially pass the baton from Smith to Peter Capaldi (who was teased briefly in this special.)
It's been a great 50 years. Let's hope there's 50 more (and beyond).