Also read my post regarding this. It contains an important note regarding your privacy/email:
http://shoutbox.menthix.net/showthread.php?tid=63...d=741925#pid741925
As you know, you can be added to a group conversation with total strangers. This makes that those strangers will also know your email address from that point on.
The script talked about MattyRid (and created by NiteMare) will not prevent that from happening. The script will actually allow you to be added to a group conversation, but will immeditaly close it again. This isn't a good protection at all.
Messenger discovery intervenes at protocol level. This means that a group conversation will not be created on your side. However, those strangers could still get your email if they use packet sniffers. So it isn't fully privacy proof either (though it is the best you can get for now).
Also note that the WLM team has personally been notified about this privacy problem (this was one of the issues addressed at the MVP summit in March). But it is always good to again submit a feedback about this to keep them reminded. You can use the feedback form for this, located at Help > Send Feedback.
The more people do this, the quicker something is done about it...
/ 
