contenteditableis not supported in Safari on iPhone OS. If you're usingcontenteditableto enable text input within a styled element (for instance,<p contenteditable>or<div contentediable>), you can replace this styled element with a styled<textarea>. In Safari on iPad, iPhone, Mac OS X, and Windows, you can customize the appearance of<textarea>elements using CSS. If necessary, you can even disable any platform-specific, built-in styling on a<textarea>by specifying-webkit-appearance: none.
Surprising. You can't use rich text editors with your fancy iPad. So, SOL on that one. Seems like a glaring omission that I hope they rectify in iPhone OS 4.
Sadness.