When I plug in my iPad or iPhone (USB), iTunes frequently recognizes its presence. BUT, nearly as frequently, it doesn't seem to notice the device at all. Un-plugging and re-plugging does no good. The only thing that seems to help is quitting and then re-starting iTunes -- which I seem to need to do more and more often any more.
iPhoto, BTW, seems to always recognize that a new device is present.
Ideas?