Debug over Wifi
When you unplug a WP device from your computer while debugging, you get an error message that the device on an IP address and port is no longer responding. If the debugger connects to the phone via IP, then why not allow for debugging over the local network? That way, someone can develop for Windows Phone in a Hyper-V VM, and still debug on a physical phone, just without plugging it in. There ought to be a way to build a Debug Agent app that can broadcast itself to the network so Visual Studio knows where to look.
Robert McLaws commented
Or you can simply put in the phone's IP address on the network, just like you have to with the Visual Studio Remote Debugger. That information is easy enough to gather.