This is all I've heard since the initial announcement,from his website <rinpoche.com>:
" Urgent Update re: The Vajra Vidya Seminar 2012, Sarnath, India
I regret to inform all concerned that Thrangu Rinpoche will not be able to teach during the VVI from January 14-23, 2012. He is recovering well now but his doctors have ordered him to have complete rest and quiet for some time. Rinpoche is now in retreat and getting the care that he needs for a complete recovery. Rinpoche wishes the seminar to continue so Tulku Damcho Rinpoche and the Khenpos of the VVI will be teaching on Gampopas "Precious Garland of the Supreme Path". Rinpoche’s translator/scholar David Karma Choephel will hold a daily review of this teaching.
Tulku Damcho will give White Tara Empowerment and teachings on that practice . See Tulku Damcho biography and photo.
Yours in Dharma,
VVI Seminar Coordinator
December 9, 2011"
"All the sublime teachings, so profound--to throw away one and then grab yet another will not bear even a single fruit. Persevere, therefore, in simply one."
--Dudjom Rinpoche, "Nectar for the Hearts of Fortunate Disciples. Song No. 8"