Found this article suggesting that Steve Jobs demoed a Flash enabled iPhone at WWDC 2008. Reading further, that's not the case, but it was... revealing.
The demo was a side by side comparison of nationalgeographic.com being downloaded by old iPhone vs. iPhone 3G. Both worked and got the NG homepage... but not really.
You see, the Nation Geographic homepage uses Flash. And if you don't have Flash, you'll see this placeholder & link:
See, this presentation requires Flash. Good graphic, well done.
But the iPhone demo, the one that puts the entire internet in your pocket, got this instead:
As you can see, someone (*cough, Apple*) edited out the text that states Flash is missing. Yet this is a "live side-by-side demo" of the iPhone browsers.
So, not a real live demo, and not really the NG website.
To paraphrase Ferris Bueller, "I yell rat!"