In his blog on IGN, Perry mentioned their studio invitation which included plenty of multiplayer action as well as a glimpse of the single player campaign. These same magazines (according to Perry, no websites were invited) will be releasing issues with their impressions as early as the end of October. Not surpsingly, the magazine's early reviews of Halo 3's multi-player were excellent, though that's all the details that are currently known.
While this news is certainly exciting, perhaps the most intruiging part of the information is that the development of the game is at a point where it would be shared with the mainstream press. This could be a major clue in just how far along the game is and it will no doubt leave fans speculating even more on when the game's release date. Remember that at this year's E3, Bungie employee Marty O' Donnell mentioned that the multi-player could have been shown then as well. We'll just have to wait a few more long weeks to read the impressions for ourselves.
