I hope that as developers we're able to take advantage of this conversational style. At the moment, WP apps can hook into the rather limited "Tell Me" system that lets the user open various endpoints of an app via voice commands, and only using pre-defined parameters.

It would be awesome if the user could pass in any arbitrary data via voice commands (devs could make custom scheduler/todo list/note-taking apps that can receive data from Cortana), and even more so if voice commands could launch background tasks instead of just the entire third-party application (you could check into Foursquare without actually opening the Foursquare app and disrupting whatever you're doing).