I'm excited about the new devices that we are getting in music. I've already looked at many of the applications for the iPhone and iPad. I really see a use for the devices and apps in my Music Theory AP course. There are quite a few apps on music reading and music theory. I am disappointed that many of the apps are currently for the iPhone and not the iPad. Hopefully in the future there will be more available for the iPad.
I know that in the professional world that the iPads are being used in place of actual sheet music. With a controlling device that these iPads are sync'd to, you can change an arrangement on the master computer and instantly change it on all of the parts. This would be an exciting (and challenging) way to rehearse and work on music.