It also illustrates that to be successful, an electronic music store must be well balanced and dynamic, easy to use, integrated with music devices -- in this case, the iPod and iPhone -- that are an established part of the popular culture, and filled with as broad a catalog of music as possible. A store also has to navigate the competing needs of recording companies and users, as well as the laws of any country in which it operates.

The success of the iTunes Store shows that even if Apple hasn't concocted the perfect formula, it's the best of the various options offered so far.

ITunes -- the application, not the store -- gained a lot of new features over the course of 2008. First came the addition of that could be played on iPods, iPhones and high-definition TVs via Apple's set-top box, the Apple TV. Then there was , allowing it to serve as a mechanism for buying, installing and managing iPhone/iPod Touch applications.

Finally, in September, that included the Genius feature that allows users to build smarter playlists and find new music based on their current libraries. While similar offerings were available in other media tools, Apple went a step further by building the technology into its latest generation of iPods, the iPhone, the iPod Touch and the Apple TV. And with an eye on where media is going, rather than where it's been, Apple beefed up the support for hi-def content available from the iTunes Store.

You say unibody, I say MacBook