Xbox 360 Fanboy found this Flash document on Intellisponse's servers, which is an online research and web-survey platform. It shows off a picture of a bunch of Mii-like characters called Avatars, that (according to the text above it) are supposed to be for the Xbox 360 and are used instead of the gamer picture. It's unclear whether or not this picture is a survey, but seeing as Intellisponse is a survey and the picture looks a whole lot like a survey, it's probably a part of a survey.
That doesn't mean that Microsoft's not working on this and isn't rolling this out at the end of the year, however. Plus, when you try to copy the URL, it feeds you a "Copying this information is in violation of your Legally Binding Agreement of Non-Disclosure," which of course we've never seen or signed. We'll see what it means come E3. All we want is to be able to use the Xbox Live Cam to face map our mugs onto these things. PLEASE. [Intellisponse via Xbox 360 Fanboy]
Update: Kotaku's got some more details on this leak. These avatars are supposedly insertable into various arcade and retail games, as well as able to swap out clothing options. Still no word on facial mapping! [Kotaku]