I really like the episode, but I had one issue: IMO, I don't see Spock changing so fast. I can see a gradual change. But for him to all of a sudden switch and see goodness immediately after "our" Kirk's departure was just too much. And then, he got others to join his cause at the drop of a hat?
I'm gonna assume these "good" thoughts were already there, and "good Kirk" brought them to the surface (in a hurry it would seem)
You're probably right, but I suppose in the interest of time, they had to advance the plot to get it under an hour. The other thing to consider, for an in-universe explanation, is that Vulcans are logical in their thinking. They wouldn't take time to mull it over as humans would. If Spock could see the logic in the new line of thought, I could believe he would switch his allegiance much quicker than we would.
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Just wanted to add that a fun thing to do is watch the original "Mirror, Mirror", and then "Fairest of them All" back to back. You really get a sense of how well the new creative team matched the sets, lighting, and costuming as well as the flow of the story. It plays out like a movie, and is a much better way to spend the evening than watching Abrams' Star Trek...
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