The update is primarily designed to add support for the iPhone to existing iTunes installations, but UK users may be more interested in a less well-promoted feature included within the new software for the Apple TV.
Responding to frequently-aired criticism, Apple has improved AppleTV by making it capable of sharing digital photos from any computer in the house using Apple's television companion.
Previously, the AppleTV has been limited to only showing images taken from one iPhoto library it is set-up to synch with.
For those users in the US with an iPhone, iTunes 7.3 lets them access the activation service for their phone and syncs it with music, movies, and other content using iTunes.
System requirements include Mac OS X v10.3.9 or Mac OS X v10.4.7 or later.