I am actually a big fan of anthologies. I have the theory that, by sheer odds, you're eventually going to hit ONE story that you like in it. And I did. In fact, there were a number of stories that I liked in it. I really liked the one by Rainbow Rowell, though probably more so because when I went to see her at Politics and Prose, she read it.
If you ever get the chance to hear an author read their own work, do it. It's SO MUCH BETTER than what happens in my head (and what happened there was pretty good.)
Some were definitely better than others, because you have twelve authors and while some are great authors, not all of them are meant to be short story writers. David Levithan's was not one of my favorites. I love him, and I liked his better when I heard him read it out loud, but I still didn't enjoy his story as much as I have enjoyed his books.
But probably my favorite out of the whole batch was Gayle Foreman's. It was funny and poignant and sweet and just a great story. I thought it was well done and one of those stories that was satisfying where it ended but still full of potential.
The book was a good anthology, and definitely worth reading, especially if you're just looking for a nice Christmas book.
I promise, one of my New Year's resolutions is to read every single Review Me Twice book beginning to end. But it's still 2014, so I didn't finish this one. What I did read, though, I really loved. My favorite thing about anthologies (other than what Cassy mentioned above, finding at least ONE you like) is how different authors take different approaches to the same theme or topic. I think a major reason why I didn't manage to finish this book on time was that I had to put it down between stories (and there are a lot of stories... twelve, so sayeth the subtitle). I don't read different authors' short stories back to back. When the anthology is all the same author, I can read straight through, but I have to do that thing where you put it down and digest what you read before I can pick it back up in the multi-author situation.