Here's what Apple said:

iPhone contains the most sophisticated software ever shipped on a mobile device, and finishing it on time has not come without a price — we had to borrow some key software engineering and QA resources from our Mac OS X team, and as a result we will not be able to release Leopard at our Worldwide Developers Conference in early June as planned.

Leopard will ship in October instead. The statement, attributed to no one but written in a distinctly personal voice, concluded by saying "We think it will be well worth the wait. Life often presents tradeoffs, and in this case we're sure we've made the right ones."

I know little about the Mac market aside from the fact that Mac people are fanatic loyalists. If I were calling the shots at Apple, and I had to make a tradeoff between getting the tasty iPhone out the door in tip-top shape or upgrading the Mac OS, I'd make the same decision. The fanatics will wait (and may even be glad to wait, judging from the Mac publications I have perused), but the iPhone could change the course of communications.

The evidence attesting to the iPhone's hotness keeps mounting. Earlier this week, Piper Jaffray released its annual survey of teenage buying habits and one surprising finding leaped out of the usual adolescent consumer pulse-taking: 25% of teens who said they know about the iPhone would be willing to pay $500 for it.

Perhaps even more startling is that 84% of teens say they've heard about the iPhone. With this kind of buzz — in the right demographic, no less — the iPhone will definitely dominate summer headlines.