David King blogged that we have draft documentation online for the Maemomm (C++) API for Maemo 5.
The text needs to be filled out a little and corrected here and there. But we have figured out how to actually use the new widgets, as shown by our example code. And the list of screenshots of the examples is probably the first time you’ll see most of the new Hildon widgets all together. It’s radically different to the previous Maemo UI, rightly so.