First, this isn't really an announcement. They aren't for sure saying that Retro will have a new big game revealed at E3. It's just one guy mentioning it on a podcast.
Second, we already know that Retro is working on something, so doesn't it make sense that they would announce it at E3? And I don't think Nintendo would give them another remake to work on, so we can be sure the game will be pretty big.
Third, nothing new here.
# of games above 75 on Metacritic (including downloadable):
360: 241 DS: 144
PS3: 152 PSP: 126
Wii: 85







