There appear to be three ways to do deep links on the iTMS without rolling your own URLs: one is to drag any hyperlink (not individual music tracks, but underlined artist or album names) to an application that supports drag and drop. You can also right click on a hyperlink or an individual track and choose the Copy Music Store URL option. That’t how I constructed the links last night. Doing either one results in a hyperlink using HTTP that goes to phobos.apple.com.
The third is the iTMS Link Maker, a web app on phobos.apple.com that walks you through a wizard to build links and gives you a JavaScript-based URL to go to the link. It also incorporates an IE plug-in control called the iTunes Detector that is loaded as part of the JavaScript solution that makes clicked hyperlinks behave “intelligently”—that is, when clicked, the links either open the selection in the iTunes Music Store, or take the user to a download page where they can get iTunes if they don’t already have it installed.
I’m less enthralled with this for a number of reasons. Number one, it requires embedding the script detector in the head of each page that bears the links—not a big deal when all pages on your blog are generated dynamically, but still something of a hassle. Number two, the iTunes Detector may be a lightweight piece of code, but it is not a lightweight user experience. I think I would rather have a link fail than pop an installer dialog over my blog pages.
That said, I’m not sure the direct link methods are any better of a user experience. The page on phobos.apple.com that is opened by these methods calls iTunes and then sends the user back to the calling page on Internet Explorer for Windows; on Safari, it appears to automatically close the calling page or tab. (Verification welcomed; I’ve only tested on my own machine.)
(Updates: See the comment from Greg about pulling a direct link from the deep link tool, and see the expanded version of this post with context at Blogcritics.)