Runsupport saidA buddy of mine has an iphone that he uses when we go run. First off its so big and akward that you have to figure out what to do with it while you run. And then it tends to be dramatically inaccurate for whatever reason. I can judge our distance and pace by time and instinct better than his iphone.
That's one of the reasons I still prefer a small cell phone. It's not an albatross around my neck, and it's the one thing I MUST have with me, if I have anything.
My Palm PDA is also taken along at other times. I can't function without my calendars and all that info. It can dial the cell phone for its 1000 contacts via BlueTooth, so together they become a sort of a 2-piece smart phone. And the Palm also has GPS and WiFi Internet, and features the iPhone doesn't have, but no streaming video stuff, which I don't want anyway.
I'd like a smartphone all-in-one solution, but until there's a very small device available, I'm still waiting.