Quark Soup points out that the libertarian-conservative-republican (US) magazine National Review has a cover article conceding the reality of anthropogenic warming. You have to subscribe to read the article (I intend to read it over coffee at Borders, frankly) but here's the (current as of this posting) link for confirmation.
Update: The web is pretty cool sometimes. Apparently the author has written in with a link to a PDF of the article.
All they tell the nonsubscriber is this:
It is no longer possible, scientifically or politically, to deny that human activities have very likely increased global temperatures; what remains in dispute is the precise magnitude of the human impact. Conservatives should accept this reality — and move on to the question of what we should do about it. This would put us in a much better position to prevent a massive, counterproductive intervention in the U.S. economy.
By Jim Manzi