I actually teach an advanced iPhone development course, for which the videos are available for free on iTunes U. The course notes for the spring and fall semesters can be downloaded in VoodooPad format.
This course is intended to follow on the many excellent getting-started resources out there. I decided to focus each class on a specific framework, so that I could explain the base concepts and common situations you might run into in each area. However, there simply isn't enough time to cover every possible case that people might be interested in, so I make sure to point out all available supplementary resources that I know of. As others have pointed out, topics like OpenGL ES could sustain a course by themselves.
The class listing for my fall semester course looks something like the following:
- Introduction / Design of iPhone applications
- Understanding Cocoa / Handling multiple OS and device versions
- Debugging / Unit testing / UI Automation / Development tools
- Views and controllers / iPad
- Quartz 2D drawing
- Core Animation
- Core Data
- Touch events, the accelerometer, and scroll views
- Networking
- Camera and video processing / Playing audio and video
- Performance analysis: memory, CPU usage, startup time
- Multithreading and multitasking
- OpenGL ES
- Core Location / MapKit
- Selling iOS applications
Again, you can check all of this out on iTunes U. I'm sure there are areas where I'm lacking coverage, simply because they're not subjects that I've used within my own applications, and therefore I'm not as familiar with them.