[Jeritron]

It was a brilliant finale on so many levels. It gave us one final twist that completely defined the alt. universe as such an amazing portion to the story/ending.
I can't wait to go back and watch it again and notice things. I just thought about how awesome it was that when they all went in the church to move on, Ben opted to sit and wait outside and think about what he'd done.

The Jack arch completion was unreal. Perfect. I love that his last act was the ultimate "I need to fix things." I love that it didn't happen right away when he put the stone back either, and it sort of made you wonder if his destiny was going to be fufilled. Then the light came on and the water poured over him.
When I saw him stumbling into the bamboo area it hit me how perfect it was going to be. Having him see the plane getting away and the eye closing were the two perfect final strokes.

MIB's plan ultimately succeeding, but costing him his powers long enough for him to get killed. Genius.

I love that the Island continued on with Hurley and Ben. Hurley wasn't exactly the person I figured would get left in charge of the island, but since they didn't show much after that point, it wasn't really major, so in that respect it was a good choice. Jack always liked and trusted him. Ben belonged on the island, so having him stay and help was another great choice.
Kate and Sawyer leaving was important seeing as they lived. I felt one of them taking over wouldn't have been as good. Sawyer is a bit too hard, and Jack knowing Kate got to go home was a big part of his ending.

And it was awesome how many great lines and shots were incorporated naturally to pay tribute the series as a whole.
Jack and Fake Locke looking down the waterfall as it panned like the hatch at the end of Season 1 was immense. Tons of great lines and sayings from the show got worked in.

Even the enlightenment scenes in the afterlife were a clever device to revisit past moments in the finale, while coming naturally the story and not serving like a clip show/nostalgia fest.

Just generally thought it was great in every way. Better than I'd even expected really. Finales are usually disappointing in some way, and even though I had faith in this one it was a concern.
It ended up being perfect for me.