One of Time's most popular bloggers, Andrew Sullivan is leaving the magazine to join The Atlantic.

From the release:

David Bradley, chairman of Atlantic Media Company, together with James Bennet, editor of The Atlantic, announced this evening the addition of Andrew Sullivan to the staff of The Atlantic. Sullivan, former editor of The New Republic, author and blogger, will join the ranks in February as a senior editor.

In his farewell post, Sullivan writes:

If it seems odd to leave a place that has been so good to me, and to the blog, that's because it is. Time's editors were wonderfully supportive and never touched a word. I'm immensely grateful to them....But every now and again, an offer comes your way that seems so right a decision makes itself. There is no better proprietor in America than David Bradley, whom I have known and respected for years. And I know of no editor I'd rather work for and with than my old friend, James Bennet, who is the new editor of the Atlantic. Their combination of talent and integrity is very, very rare, and I'm lucky to join them.

But, many will still wonder if the decision is, at least partially due to some of Time's recent struggles. Then again, their web traffic is up...