lopossum was quite harsh in his criticism but he does have a glimmer of a point. The Cocoa tutorials once were in-depth and inspiring, but now they tend toward the basics. I don't mind so much since I do access those other sites you intimate, but it would be nice to get the same depth from O'Reilly since I really like the site.
Of course a zero code browser tutorial must be done but even at my basic level, I've done this on my own as soon as I installed XCode (it is that easy). What I and lopossum and others like us might appreciate more would be a deeper look at WebKit, like how it interprets and renders html content. I think a small(ish) split view html editor tutorial would be awesome. I would be very willing to read through four 4 to 6 page installments for something like that.
I hope I don't sound like I'm "insulting your family," I would just like to think that O"Reilly is capable of serving the basic, intermediate and advanced developers/hobbyists who visit their site.