I gave it an A-. I'll say what I said on facebook. It's long and schizophrenic, but it's also entertaining, familiar, and has a good heart. When we got to the Misty Mountains, I definitely thought "ah fuck, we're only at the Misty Mountains? This has been going on forever." But the odd thing is I wasn't bothered by any scene previously. Everything felt well-paced and exciting. I certainly could think of a few things (pair down the Trolls, cut the Azog killing a henchman scene), but nothing that would have changed things much.
Of the additions, I liked them. I was surprisingly pleased about Radagast. He fit the tone of the story fairly well and better him as comic relief than Gimli in the Two Towers. Azog also worked well and gave the story a sense of urgency in what was otherwise a bunch of disjointed vignettes.
The tone was the hardest to get used to, but it was the more Hobbit-like parts that felt odd and I can't fault him for at least trying to be a bit like the book in that regard. I also can't really fault him for trying to bridge the gap to the LOTR with the bits that are more serious. It would be nice watch the movies together so I don't want the tone to be too jarring. Plus, considering Tolkien's rewrite, it seems appropriate.
The HFR took a little bit to get used to (at first, I thought it was playing on the wrong speed), but it quickly seemed to get better. I got a slight headache right around the Misty Mountains, but I think eye strain had something to do with it. Overall, I felt it was roughly Two Tower-like. A bit padded for the material, but still entertaining. Plus, I felt the story had very good themes. Not just the maturation of Bilbo, but the Dwarves finding their home thing.