To go along with Mac OS X Yosemite, Apple has now released iTunes 12.0.1 through the Mac App Store and directly through the Apple website. The update comes in at around 218MB and features many new design and performance improvements that Apple says makes iTunes more enjoyable to use.
Additionally, Apple has also released a security update with the iTunes release. Security Update 2014-005 is recommended for all users and improves the security of OS X although, Apple hasn't yet revealed what has been fixed according to their update page here.
