https://gmatclub.com/forum/mit-lgo-fellow-applicant-for-lgo-program-starting-in-88783-60.htmledzo83
Check the link above, it is the thread for the LGO applicants who started in June 2010. Click on the 4th page of the thread and in there, you will see that there was a wave of invitations for International Applicants sent out on the 21st of January. If this holds true, then this friday or this upcomming monday, some international invites could be extended.
Also, look through the thread (URL above) for username "LGOgirl." She is an international student and got an invite for interview on the first wave with most of the applicants. She got it through the mail. I assume that there might have been more international applicants who got invited to interviewfest on the first wave, but I was also told that most international applicants admitted did not go to Interviewfest (Most meaning 4 out of 5).
Because of this, I strongly believe that most international admits do not go to Interviewfest. Also, I am speculating too much about the dates. This year seems to be different than the past two or three and thus, a wave of invites comming this friday or monday may not happen. They will come later.