According to Sony on January 8, 2008, December 2008 will see in-game XMB available on the Playstation 3, a feature similar to Xbox 360's in-game guide feature, a much wanted feature that consumers have demanded since launch. The demands stem from the fact that unlike the Xbox 360, music stored on the console's hard drive cannot be played while playing a game, and if a message or game invite is received during play, the game must be exited before they can be read. Sony Computer Entertainment America (SCEA) and many other sources state that in-game XMB is the single most requested feature for the PS3 in the last year (2007).[6] Sony handed out "In-Shirt XMB" t-shirts on February 19, 2008 at the Game Developers Conference (GDC) held in San Francisco's Moscone Center.[7] Basic forms of In-game XMB friends lists can be found in many modern (August 07' or newer) PS3 games including; Resistance: Fall of Man (Since the 1.1 patch), Warhawk, Rockband, Call of Duty 4, Burnout Paradise (also includes In-game XMB headset accessory menu). In addition, custom soundtracks, taking on the user interface of the XMB has been implemented into a few games such as Super Stardust HD and High Velocity Bowling. These partial functions of XMB (friends lists and custom soundtracks) have been up to the developer to implement the function. The true in-game XMB won't be debuted until Summer.[