With the release of Snow Leopard only a short time ago, many of Apples internal applications, save for a few such as iTunes and Front Row, have been rewritten in Cocoa and built as 64-bit applications. The reasons for doing so range from reluctance to retrofit major new features or fix old bugs in an application due for a Cocoa overhaul, to the obvious advantages that come with 64-bit computing; access to larger amounts of memory should it ever become necessary, and new processor features only available in 64-bit mode.

While Apple is no doubt still working on porting their flagship application to 64-bit Cocoa, the release version of iTunes 9 available from the Apple Website is apparently still 32-bit only. Read more