How does Google crawl the iTunes Store?

Last I checked, a web page had to be on the web in order for Google to crawl the page and serve it up in search results.  But then how does it crawl iTunes?

On a recent search for “implus iphone application” I came across the iTunes store page ranked at #8 in Google.

Yes, the iTunes Store may be built on WebKit, or some sort of web application on the back end, but how exactly does Google get there?  Does the Googlebot run iTunes?  Ohh there is a possibility.

I checked the cache version of the page and it’s just text on a basic white background.  Looking at the source of the cache it appears that’s it’s an XML document.  Apple is feeding Google XML documents for iTunes products!

Now that’s pretty smart.  Not sure if it’s really fair as you can’t get to the page without iTunes, but it not only helps Apple but all the products in the iTunes store as well.