* 505 Games
* Activision
* Advanced Micro Devices
* Atari
* Atlus U.S.A., Inc.
* Bethesda Softworks LLC
* Capcom Entertainment, Inc.
* Crave Games
* Disney Interactive Studios, Inc.
* Electronic Arts, Inc.
* Epic Games, Inc.
* Konami Digital Entertainment, Inc.
* LucasArts Entertainment Company LLC
* Majesco Entertainment Company
* Microsoft Corporation
* NAMCO BANDAI Games America Inc.
* Natsume, Inc.
* Nintendo of America, Inc.
* NVIDIA Corporation
* OnLive, Inc.
* Perfect World Entertainment
* Proximo Games
* Sega of America, Inc.
* Sony Computer Entertainment America Inc.
* Sony Online Entertainment LLC
* Square Enix, Inc.
* Take-Two Interactive, Inc.
* THQ Inc.
* Trion Worlds, Inc.
* Ubisoft Entertainment
* Warner Bros. Interactive Entertainment Inc.
By the way, the ESA tells us online registration is open for media and attendees. And if you're hoping to scalp a badge, think again: the ESA told Gamasutra that they won't be mailing out badges ahead of the show this year to curtail badge-selling.