The iPhone just got a little bit more powerful — an application that turns your iPhone or iPod Touch into a remote control for iTunes and Apple TV has gone live.

The previously rumored application is available as a free download through the new iTunes update, version 7.7, which is being rolled out just ahead of the iPhone 3G’s U.S. launch tomorrow. This version of iTunes is expected to include the App Store for iPhone applications.

As MG Siegler just noted, Apple is even promoting the remote control app on the iTunes update page, so the company sounds pretty excited about it, and for good reason. Being able to search your iTunes library, surf on Apple TV and control your AirTunes speakers already brings the iPhone pretty close to controlling your entire home entertainment system, at least if you’re a hardcore Apple fangirl or fanboy.

I’m definitely going to be taking advantage of this myself. I just need to update iTunes first — oh yeah, and buy an iPhone.

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