Nate Silver (the NYT quantitative political analyst) and Dave Weigel (the Slate columnist) have started a good tradition, listing their worst predictions of 2011. (Silver also listed his best.)
If any other pundits are doing the same, link them here.
Update: Gwern is working on this with me. The result will be a CFAR blog post.
Apparently a team at Penn is doing this as well:
http://jackman.stanford.edu/blog/?p=2602