Microsoft has said that the Twitter and Facebook applications planned for Xbox 360 will be separate applications rather than part of another broad dashboard update.
Microsoft marketing type James Halton, speaking at an event earlier today, told Eurogamer the company is targeting an "autumn" date for integration of the social networking / tedious showing off sites, but wouldn't narrow it down.
However Halton did go on to say, "It will be before Christmas." He added, "A lot of the background work's been done for a lot of applications that are coming."
We already know they're not in the August dashboard update, which has been extensively detailed and goes live on the 11th.