I'm the last in line for this week's theme, so it's entirely possible someone else will have picked the same thing, but not likely for the same reason.
After much thought, I'm picking the New 52 as the best of 2011. I only read a fraction of what came out in this magnum of number one issues in September, and only 1 issue of any of the books for any of the big players (Batman, Superman, Green Lantern, JLA). I don't budget like Mr Deep Pockets (you know who I mean), who bought all 52 first issues. As a result, it can easily be argued that at least half of the 52 titles are ought but crap. I wouldn't know.
However, there are two reasons for me to consider the New 52 the best of 2011. First, by the time DC embarked on this re-launch I was down to one title a month (the late, lamented Secret Six). Now I'm buying about a quarter of the 52 titles, and actually expanded from my initial purchases by adding I, Vampire and Demon Knights based on favorable comments by others. So far I haven't dropped any of the titles I started with the new launch, so that's a pretty big deal for DC. Not that my personal buying habits are all that important to DC in the grand scheme of things, but if it represents a greater trend, then it is very important to DC.
The second reason is more personal to me. Among the new titles I'm reading from the New 52 are Brian Azzarello's Wonder Woman and Jeff Lemire's Animal Man. These were such good reads that I picked up Lemire's Essex County collected edition and Azzarello's Spaceman that's now coming out in singles from Vertigo. I enjoyed those so much that I then bought trades of Lemire's Sweet Tooth and Azzarello's 100 Bullets and Loveless. Now, this last title may be a bit of a problem, but all the others have been great so far (and will be subjects of posts some time down the road).
For expanding both DC's sales and my own reading catalog, and particularly for bringing two really good authors to my attention, the New 52 is the Best of 2011.