A pre-release version of iTunes 7.7 was issued by Apple for developers. The Read Me file of the iTunes installer gives a hint at a previously unannounced iPhone/iPod Touch application. Here's what it sais:
"Use iTunes 7.7 to sync music, video, and more with iPhone 3G, and download applications from the iTunes Store exclusively designed for iPhone and iPod touch with software version 2.0 or later. Also use the new Remote application for iPhone or iPod touch to control iTunes playback from anywhere in your home -- a free download from the App Store."
Apparently, they'll be offering a free application on the App Store that will allow users to remotely control playback of iTunes in their home from their iPhone or iPod Touch, most likely via Wi-Fi.