As a non-programmer with a thorough mental block on Obj-C principles can attest, these lessons have been a godsend.
Mike had some excellent Cocoa articles written, but I could barely understand half of what he wrote. After these simple lessons, the Cocoa concepts are becoming much more clear. I am even able to explore new concepts and learn them on my own.
Cocoa is great. Seth is bringing the rest of us up to speed so that we can all enjoy it. This article darn near puts C basics to an end and forces the next step where Mike started from.