Specifically, the firm claims the unannounced game will pack "over 400 cars and 100 tracks."
The information comes as part of massive data leak from Intellisponse that was documented by NeoGAF. The company's clients include Microsoft, Activision, and many others. As Intellisponse is a marketing research firm, this data could represent market surveys or test concepts instead of actual facts.
The documents also note that Microsoft is toying with the idea of a collector's edition that would include a "special VIP program that would entitle the user to all future Forza 3 downloadable content, access to exclusive online race events and prizes, extra server space" and more.