This year the reading went quite a bit differently than usual. The biggest difference was, I had already read several of the stories from other sources. In particular, the excellent Cory Doctorow story and one of the Elizabeth Bear stories were in the excellent "Hieroglyph" collection with I reviewed here; the Lauren Beukes story was in the "Twelve Tomorrows" collection I reviewed here; and the Peter Watts I had purchased as a $1.99 novella.
The last story of The Year's Best is usually a very strong novella. This year's last story was a first contact story by Nancy Kress. Ms. Kress is a top writer and I don't remember not enjoying her stuff before, but this just wasn't a strong effort. Minor twists on the 1st contact theme were OK, but the characters were mostly unlikable. Plus the volume had already had a completely off-the-wall and unique 1st contact story: "Thing and Sick", by Adam Roberts. In addition to being unique, this story was really creepy as well.
There were some other good stories. The Robert Reed was interesting. But all, in all, I think I'd have to pick those other two collections together, "Hieroglyph" and "Twelve Tomorrows", as the year's best.