After releasing OS X Lion earlier toady Apple drop an update to iTunes which will be 64-bit and will boast full-screen support
What’s new in iTunes 10.4
iTunes 10.4 is now designed for OS X Lion.
You can now use iTunes with OS X Lion’s new Full-Screen App capability, which allows you to use iTunes and other apps without distractions. Navigate between full-screen apps with a simple gesture.
Note: iTunes is now a 64-bit Cocoa application on OS X Lion and includes a number of important stability and performance improvements. Some iTunes plug-ins may no longer be compatible with this version of iTunes. Please contact the plug-in developer for an updated plug-in compatible with iTunes 10.4