Rare: Avatar development started pre-Mii

Rare, developer of Microsoft's Avatars, explains that any similarity between its creations and Nintendo's Miis is purely coincidental. In an interview with Eurogamer, the company's art director, Lee Musgrave, states that Rare was working with the idea of Avatars (not necessarily for the New Xbox Experience) before Miis were part of the gaming landscape. Microsoft apparently liked the idea enough to make it part of its dashboard overhaul.

Musgrave makes it clear that Microsoft didn't show up one day and ask for a counter to the Mii. He claims there were many questions about what form the Avatars should take (animals, Spore-like creatures, ultra-realistic humans), but they eventually landed on something that had "approachability." Apparently, Nintendo agrees.