At the August meeting Daniel Steinberg will provide an overview/intro to using blocks.
"Whether it's the funny looking syntax or the difficult retention rules, it's time for you to overcome your fears and embrace blocks. In this talk we'll look at when and why we commonly use Apple's block based APIs in our code and then examine concrete examples of when and how we should introduce blocks into our own classes. This session shows iOS developers the fundamentals of creating and using blocks to better accomplish tasks with collections, completions, callbacks, and concurrency."
UPDATE: B.J. Miller will be telling us how he recently used an NSFetchedResultsController with a map view instead of a table view.