Welcome to the Netduino community!
There are three new pieces of code required to get bi-directional comm up and running over USB.
USB/serial deployment selection:
Completed (part of the new v220.127.116.11 firmware)
USB HID C# library for PC and Netduino:
UsbClient update to Atmel .NET MF C++ code:
In development (Secret Labs + Atmel + Microsoft + community)
So we're most of the way there...but one piece to go. Once v18.104.22.168 ships next week, we'll be doubling down to coordinate the necessary fixes to enable a few different PC<->Netduino communication scenarios.
This is great. Thank you for keeping us posted on this.