The last episode was so rich and full of great stuff. The two scenes between Kevin and Matt were extraordinary. I have been following Christopher Eccleston's career for awhile now, and this is the best work I've ever seen him do.
Kevin's crazy dream and subsequent meeting with Wayne. His wish, granted. Laurie had so much going on in her initial "talk" with Jill, and her obvious regret about it later. Her faith seems to have been dashed while Meg, on the other hand, has grown more and more defiant. Tommy brought the baby to the one person he knew he could count on, and just before leaving found his mom again.
And Nora, geez. I have never seen anything like that before -- the actress was amazing. Everyone brought their A-game to this. And I haven't even mentioned the music, both needle drops (the Metallica song, Nina Simone) and the score, which were both of the amazing caliber we've come to expect from this show.
I think this was both a great season finale, with plenty of threads to be picked up for next year, but also would have served fine as a series finale if it hadn't been, which nobody knew at the time it was written and filmed. That's a tough nut to crack, yet they did it, and very well.