Microsoft Legal has this to say about the EULA:\

To clarify the intention of Section 2.d. of the 2.0 EULA:  this restriction only applies if your program is interacting with Microsoft’s networking services, e.g. Xbox or Games for Windows LIVE service (“LIVE”).  If you are implementing a solution that does not in any way interact with LIVE then this section would not apply.  We are evaluating an unencrypted means to implement text chat in the next GSE release so that you would be able to implement text chat functionality over LIVE. 

Please note that if you do decide to implement any non-LIVE networking functionality with communication capabilities, you are responsible for comply with any applicable legal and regulatory requirements.