I sat down under a tree in my garden and read through to the end of Mockinjay:
I really thought this book was a bit of a disaster. It felt like the author didn't know where to go with the story after leaving the arena. We get a bunch of random scenarios that don't constitute much of anything happening, or story progression. When we finally DO get to the point of moving forward, she(the author) falls back on what she was obviously so proud of from the first two books. It makes very little sense.
Then we have the whole Gale/Peeta thing which kind of just drove me nuts.
I had heard that the ending was depressing, but it really didn't feel that way to me. It was a natural extension of the story. I wasn't particularly happy with it, but I can accept it. I just wish we had gotten a little more info on what's going on with a few of the characters.