Oddly enough, the thing that depressed me the most during the Acid Tokyo arc was Mokona crying. I guess I had always pictured it as being happy regardless of what was going on around it, so the sight of this cute, innocent-looking little white fluffy thing just crying its eyes out made me sad.
I think what they did with Fay's past is clever in that most of the clues you get as to what happened with him make it seem like he did something awful (I guess he thinks he did), but then he turns out to actually be the victim. All of my guesses about his past were way off base, anyway.
The whole fake Sakura thing annoyed me though. It seems like it just made everything needlessly complicated. I seriously can't figure out the explanations of what's supposed to be happening anymore... >.>
I like the clone Syaoran, and kinda hope that he somehow manages to get a happy ending... or at least, isn't insane for the rest of eternity.
Also, the Mokonas are adorable, and I want one. Or two.
Now I'm going to have to start xxxHolic again, aren't I? It's been so long since I read it that I'll probably have to start all over from the beginning. Oh well.