Perhaps the closest guess came from John Markoff of the New York Times -- about 4 years and 5 months before the iPhone came to light. In an August 2002 article, Markoff described a discussion with Steve Jobs about "a device that would combine elements of a cellphone and a Palm -like personal digital assistant." The name iPhone was used in the article, and Markoff notes that at that time Jobs felt the days of the PDA were numbered.
Markoff was close, but a stock analyst quoted by Chicago Tribune reporter Mike Hughlett was way off track. The analyst, Mark Stahlman of Caris, said that "a phone venture would be a 'distraction' for Apple."
Many of the conceptual drawings of the iPhone in the post are humorously off-base, with everything from an iPod-like scroll wheel (see above) to a very Nokia-like slide-apart device. If, or when, the Apple tablet finally appears, a retrospective look at the wacky ideas of the Apple pundits will be worth a good laugh.