Here's Bethesda's press announcement in the matter:
Bethesda Softworks Announces
The Elder Scrolls IV: Oblivion Game of the Year Edition
Expanded Version of Award-Winning Role Playing Game,
for PC, Xbox 360, PLAYSTATION®3 system Available In September
July 9, 2007 (Rockville, MD) � Bethesda Softworks®, a ZeniMax Media company, announced today that it will release The Elder Scrolls IV: Oblivion® Game of the Year Edition (GotY)
for Xbox 360™ video game and entertainment system from Microsoft,
PLAYSTATION®3 computer entertainment system from Sony, and Windows this
September. Oblivion GotY will include the original version of the award-winning RPG Oblivion along with the official expansion, The Elder Scrolls® IV: Shivering Isles™, and the downloadable content, Knights of the Nine™.
This new product will allow players who have never played the 2006 Game of the Year to experience Oblivion for the first time with additional content. In addition, gamers can continue their existing games of Oblivion and experience the new quests and areas offered by the expansion and downloadable content.
Released
in March 2006 for Windows and Xbox 360™ video game and entertainment
system from Microsoft and in March 2007 for PLAYSTATION®3 system, Oblivion
has already earned countless awards from publications around the world
and won numerous Game of the Year and RPG of the Year awards.
Gamerankings.com and MetaCritic.com list Oblivion as the highest rated game of all time on both Xbox 360 and PLAYSTATION®3 system.
Oblivion
features a powerful combination of free-form gameplay, unprecedented
graphics, cutting edge AI, character voices by acting legends Patrick
Stewart, Sean Bean, Terrance Stamp, and Lynda Carter, and an
award-winning soundtrack. Gamers can choose to unravel Oblivion’s epic narrative at their own pace or explore the vast world in search of their own unique challenges.
With more than 30 hours of new gameplay, Shivering Isles allows you to explore an entirely new plane of Oblivion � the realm of Sheogorath, the Daedric Prince of Madness. Shivering Isles
features a bizarre landscape split between the two sides � Mania and
Dementia �filled with vast, twisting dungeons mirroring the roots of
the trees they are buried within. Sheogorath himself looks to you to
be his champion and defend his realm and its inhabitants from
destruction as you discover all new items, ingredients, spells, and
much more.
Knights of the Nine
features an all-new faction and quests for noble characters and answers
many of the questions surrounding the Ayleid ruins found throughout Oblivion.
Players can join a new faction and found their own order of holy
knights � leading them into battle against a sorcerer-king and his
demonic minions while exploring massive dungeons and searching for
legendary relics � the holy armor and weapons of the Divine Crusader.
For more information on Oblivion, Shivering Isles, or The Elder Scrolls, visit www.elderscrolls.com.