Core MIDI sample code is here – http://goodliffe.blogspot.com/2010/10/using-coremidi-in-ios-example.html
This example probably actually does *not* violate NDA, because it’s the same code as you’d use on the Mac framework. (Okay, maybe I’m reaching … sosumi.)

Chris Anderson, the guy who wrote the book on [obscure fact] Java media on the Mac, has a new book on Core MIDI and Core Audio coming. Given scant documentation on these frameworks, that should be really good news for developers.