Threads on Late Night Cocoa

I saw that Mark Dalrymple made an appearance on the Late Night Cocoa Podcast discussing threading and just now had a chance to listen to it on my MBP and I must say it was a really nice to finally hear someone (other than MacResearch) give some time to discussion on NSOperation, plus I was just curious what he thought about it. Mark is one of my heros because his book Advanced Mac OS X Programming was the first mac dev book I read to treat me like an experienced developer and not someone who had never heard of Cocoa, that and the content was excellent. Im sure the next edition will be great as well whenever that comes out. Additionally he has a great mini blog and there is the occasional gold nugget in his quickies section.