Windows Phone 7 (and Windows/Mac): Just because you're on Microsoft's mobile platform doesn't mean you need to leave iTunes behind. This nifty app controls any iTunes library wirelessly, giving you power over playlists, volume levels, and song/album searching.
Grab the app ($1.99 in the Marketplace, with a free trial offered), download and install the pairing utility for Windows or Mac, and your phone's new Remote app should be able to find iTunes libraries on your Wi-Fi network (assuming you have library sharing enabled). The controls and album art are slick, the use of your keyboard to search music or playlists is handy, and you can even control the volume. And if you haven't already grabbed the Windows Phone 7 Connector for Mac, do so—you can sync your iTunes and iPhoto libraries to your computer for use when you're not near your main Mac.
iTunes Remote for Windows Phone 7 is a $US1.99 purchase, or free trial download, in the Windows Phone Marketplace.
iTunes Remote for Windows Phone 7 [Komodex]