In IE for Windows Phone, you have the ability to share a link to the current page you're on from an Application Menu Item. The options are as follows:

Messaging
E-Mail
Social Networks.

I would like the ability to easily share a link to another application. It would work in much the same way the Photo Hubs Extension works. You would see a 3rd party app that supports the Share Link extension. Clicking it would open the app at a specified task. Then, one of the query string parameters that's used to launch the task could just be the URL Encoded link to the page. The app could then do whatever it'd like with that link.

Currently the only way to share a link or text with other apps is to use the Copy / Paste feature, then head to start, then open up the app, navigate to the point of the app that accepts the text, and paste.

This would allow many other developers to feel like First Class Citizens, where as now, if you're not FB or Twitter, you're left out in the dark.