The link here indicates a more systemic problem:
Windsor explained that the screen of the iPhone uses a chemical deposition to provide touch sensitivity based on heat. The international property rights for this technology, he said, were purchased from a bankrupt Finnish company that was trying to make a similar device. But that company encountered the problem that with extensive use, the film would begin to degrade and the screen would lose its sensitivity. Windsor said the problem typically manifested itself within three to six months. While Apple should have been aware and fixed the problem, the broker said, only time will confirm that all is well with that touch screen. (link)
http://blogs.business2.com/apple/2007/08/iphone-dead-zon.html
I finally played with an iPhone for an hour today at the Apple store in NYC. They have abut 50 phones activated at tables for you to play with. I figure this phone has been out since it launched and gets played with every day non stop.
When the 3G version comes out I will buy it that day. It is an incredibly cool and intuitively easy phone. I figured out how to use each feature instantly. The screen is absolutely gorgeous, the camera is pretty damn good. Flipping around pictures is amazing. Google maps is incredible, using your fingers to pinch in and out to zoom in or out or move. I did not notice any problems with the screen. My only complaint is typing on the touchscreen is a bit hit or miss. The ‘buttons’ are pretty small and its easy yo make mistakes. However the intuitive text correction is also pretty good. I even browsed FR today!