Apps on other platforms don't interact with other aspects of your phone, Microsoft argues. App Connect will incorporate the information from each of your apps--whether it be a music app or a weather app--seamlessly into Search. So if you're searching for a movie, for example, App Connect will integrate ticket-purchasing information from the Fandango app along with your standard search results for movie times, reviews, trailers, and similar data.
Since Mango isn't out in the wild yet, developers haven't integrated these capabilities into existing apps yet. When I tested Mango in July, I tried to search for local movie times to see whether information from Fandango or IMDb apps would show up, but it didn't work yet.
App development is crucial to the WP7 platform. A severely limited number of apps won't help WP7 gain traction in the market. As of August 27, 2011, the Windows Phone 7 Marketplace had more than 30,000 apps available. That's a lot of apps, but the number seems measly when compared to the Android Market's 250,000 and the iPhone App Store's 425,000. Many developers I've spoken to over the past year have said that are reluctant to develop for Windows Phone 7 because of its slow growth in sales. Will the Mango update and these next-generation Windows Phones change that? We shall see, but I remain optimistic.