I have a NSFetchedResultsController which is fetching objects from a NSManagedObjectContext. I\'m using the results to populate a UITableView.
I haven't had a chance to dig into that area of the SDK yet (my work is with C#, so the iPhone stuff is in my hobby time), but from what I can tell you would want to use the other init, specifically initWithKey:ascending:selector: and for the selector you could pass a selector to your compare method that would only compare on the Year/Month/Day, ignoring time.
Here's the url for reference: iPhone Library Documentation
Hope this helps!