Hi Andy.
About WP8.........yes I know that it only supports NDEF thats why I mention in an previous post that we will have to take into acount the LLCP protocol. This protocol was designed by the NFC Forum, you can download the technical especifications here:
http://www.nfc-forum...cs/spec_license
The SamConfiguration you use is valid to data exchange also, I found out this Arduino code example that meets LLCP protocol to comunicate an Arduino+ PN532 Shield and an Android phone........maybe it could help us as a guide to earn to comunicate Netduino and a Windows Phone........... I attach it.