According to the Wikipedia page on the Thirst series, Thirst No. 4 will be released on August 9, 2011. :)
Thirst - 2015 was released on: USA: 2015
Thirst - 1917 was released on: USA: 29 July 1917
Thirst no.1: The Last Vampire, Black Blood, Red Dice Thirst no.2: Phantom, Evil Thirst, Creatures of Forever Thirst no.3: The Eternal Dawn Thirst no.4: The Shadow of Death
The Thirst for Gold - 1912 was released on: USA: 27 May 1912
The Thirst for Gold - 1913 was released on: USA: 13 August 1913
August, 2011.
Thirst - 2011 was released on: USA: 2 October 2011 (Sunday Night Screenings)
The Wiggles The Series - 1999 The Big Thirst What's the Best Thing About Being a Dog was released on: USA: 4 September 2012
For now, it is the season with the least amount of released albums, without counting EPs. Although a disc titled "Season 4, Volume 1" was released, no other volumes were ever released.
the osmotic pressure of body fluids, vascular volume and angiontensin
Vampires Thirst for the Truth - 1996 TV was released on: USA: 1996