There are a few details about the iPhone that still haven't been solidified. One of the most important questions (for software developers anyway) is whether or not the phone will have an open development platform that will allow users to install third-party software on the phone. You'd think this would be a no-brainer, since the phone runs a (presumably stripped-down) version of OS X, but the word on the street is that Apple will not be opening the phone to third-party software. That's a bitter pill to swallow. If it's true, it could be a huge mistake.
Somewhat less clear is whether the phone will allow the use of third-party widgets, but I'm betting the answer to this is that it will.
There's also confusion around whether or not the iPhone contains a GPS receiver. Steve Jobs didn't mention GPS in his keynote, but his demo of the Google Maps application seemed to indicate some sort of location awareness. Some websites (including MSNBC) are reporting that the iPhone does have GPS support, although this could be the result of a misunderstanding.
Jobs also made a remark during the keynote implying that the phone might have 3G support by the time it reaches Europe. The obvious question is why the hell it won't have 3G support here in the States. This is another bitter, bitter pill to swallow.
I'm on the edge of my seat waiting for answers to these questions. The iPhone really does represent a revolutionary shift in handheld gadgets, and it'll either go down as a triumphant success (ala the iPod) or a red herring (ala the Newton).
Update: David Pogue has answered most of my questions. No, the iPhone will not be an open platform (sob!); no, it doesn't have GPS; and yes, it will probably eventually support 3G, just not initially.