[Kontra]

  "I don't want to create iPhone-specific apps with Flash (yet!)."

You shouldn't. But a lot of Flash apps made for WIMP won't run smoothly or, in many ceases, at all on the iPhone.

  "All multi-touch does in Safari is zoom!"

Nothing is perfect, but the iPhone, unlike any other mobile on the planet, does in fact have a coherent user experience. And the basis of that is multi-touch, not just in Safari but everywhere on the phone. This isn't some Linux distro where all apps have their own UX paradigm. You can't expect iPhone users to switch UI paradigms when they encounter Flash apps just because Flash can't handle multi-touch or because its WIMP conventions conflict with the iPhone's. (The vast majority of Flash apps/sites are predicated upon mouse rollover, for example, that doesn't work on the iPhone.)

This is a movie we've seen before. You could give the same example with friends sending you links for stuff buried in Active X containers in IE that no other non-Windows browser could properly render. What happened? MS has gradually abandoned Active X, and much of what Active X could do can now be done via non-proprietary browser technologies. The scenario won't be so different for Flash. Nothing will be black and white, but that's the trend.