"And if webOS is basically web-based, that means that all of Palm's apps will be available on the iPhone, but none of the iPhone's apps will be available on the Palm Pre. Not exactly a winning proposition."

And you'd be right, if they do it the way original iPhone apps were done - scaled down websites running in a browser.

But not if what they actually have is a rendering engine as part of the OS and a Javascript API for things like location, sound, data, etc.

Then you have a powerful SDK that everyone and their little brother already pretty much knows how to use.