Apple released iTunes 10.4 which brings support for some of the new features in Mac OS X Lion and a number of important stability and performance improvements. iTunes 10.4 now works with Lions new Full-Screen App feature allowing the app to be placed in its own full-screen window. Version 10.4 is also now a 64-bit Cocoa application on OS X Lion, and the release notes indicate that this may render some plug-ins no longer compatible.

You can download iTunes 10.4 here.