As I understand it, you can set one of four values for the key "AutocapitalizationType" in Root.plist of the Settings.bundle: None, Sentences, Words, AllCharacters. None seems to work quite well :D, but none of the other options seem to do anything. To test each change, I save the Root.plist file, delete the app from the simulator, and the build and run the app.
Is there something I'm missing? The setup seems pretty fool proof.
On a side note, I can set the AutocorrectionType without issue.