Is Judge Posner a "conservative" judge?
The NY Times article on conservative judges criticizing Heller says so, but a post at Blakanization argues otherwise. (Read the comments, too). The argument is that Posner's method -- pretty much pure pragmatism, with no great regard for traditional tools such as textualism, original intent, construction by principles of language, etc.. I'd guess the NY Times author had trouble with the idea that "he's a pragmatist, which is neither left nor right," and went with the label that fit the story he wanted to write.
UPDATE: a humorous reference to Judge Posner during Supreme Court arguments. Go to bottom of p. 37 and top of 38. For some reason, I suspect Justice Alito and Judge Posner know each other, and Alito probably emailed him the transcript as soon as it was available.