It has been one year since the O'Reilly MacDevCenter site has published an article on Cocoa. The articles since then are a mix of various Mac OS X tips and tricks, with a heavy emphasis on Aperture—so no actual Mac development articles.
It's been quite a while since O'Reilly has published a book on Mac development, too. There is the Missing Manual series, but it is really something distinct. Has O'Reilly given up on Mac developers?