It seems Apple is quietly updating things and not making a big bang out of it.  First it was the firmware update to the new line of iPod Nanos, now its a new way for customers to view iTunes content without having to launch iTunes.  Its called iTunes Preview.

Instead of the usual links that iTunes generates that made users computers open up the iTunes application, now it redirects them to a web page that allows users to browse the selection, see track-listings and get user reviews.  It will be a great way to email recommendations of music to friends and family.

You still need to have iTunes installed on your PC in the end to actually download the music, but now, you can web browse before you buy.

Thanks AppleInsider and Macworld for the info!