Although I'm not a developer, I have been able to play around extensively with iOS 4.2 on my iPad. Let me just reiterate the sentiments that it is indeed worth the hype. With new features like AirPlay, it's understandable that that ability to switch your fonts in the Notes app is playing second fiddle to all of the other enhancements.
Although iOS 4.2 is right around the corner, Apple has been one-upped with the release of the jailbreak tweak, NotesFont. Not only does this tweak bring the ability to change fonts in the native Notes app, it offers a lot more fonts than what Apple is planning to offer...