Sony currently has a virtual world where the the realistic avatars can gather and chat. Microsoft, not one to be one-upped has come up with their own delta hub, which is somthing like a large arcade (including arcade cabinets to play, and fully customizable). The arcade games are all oldies provided by Konami, Atari, and Intellivision (Holy fuck, Intellivision is still around?!?!) with prices for either permanant access or a one time play.
Also confirmed is that Project Natal, Microsoft's venture into motion control, will definatly debut by the end of the year, though possibly with a new name. We are expected to see more at this year's E3.