As my latest foray into video tutorials, Zendcasts reaches past the 400 subscriber mark on Feedburner, I've been getting more and more requests to tackle Zend_Db. I've been holding back for a lot of the design reasons that I recently read on Angry Objects. The author identified a lot of the problems I have with the official way of Zend wants developers to handle the "M" in MVC. I've tackled this issue professionally by using Doctrine and introducing a service layer similar to what's been presented in the latest tutorials for Microsoft's MVC .NET initiative. I prefer to use a Repository (or as Leendert Brouwer calls it) a service layer. His naming is probably more correct since it generalizes the problem and doesn't get confused with the Domain-Driven Design notion of what a Repository should and shouldn't be. Regardless, I'll be covering some introductory stuff on Zend_Db, however I'm probably going to steer the zendcasts ship near Doctrine since it's my own preference.
Having said that, I'd love to encourage other developers who are doing video tutorials on Zend to feel capable of contributing to zendcasts.