I purchased the original iPhone on release day back in 2007. Since then, I've probably done 40% or so of my web surfing on it. Saturday I bought an iPad for my father, who is currently in town visiting. After helping him set up email (damn you charter for being such a pain in the ass to work with), I went to look up some settings using my iPhone. It seemed so small and useless. After 2.5 years of using is extensively, I was thoroughly amazed at how cramped web surfing felt after using the iPad for 10 minutes.
Can't wait for my 3G version to arrive... on a plus side, my wife was so blown away by it she's going to go get one too.