I just now discovered an annoying behavior with Blogger and my new blog syndicated to Planet. Apparently every time I edit an old post, it bumps a field in the atom feed that causes Planet to bump old posts to the top. This old post indicates this has been a common problem with Planet in the past. Is this a bug in Planet, miconfiguration in Planet, or a bug in Blogger?
UPDATE: Add ?alt=rss to the Blogger feed URL and it solves this problem!