Major Nelson's Twitter feed, the dashboard update is being pushed to accounts in batches, and should be widely available over the next few hours.)
After Microsoft announced several new services would miss the December 6 launch of the Xbox dashboard update, it has revealed that another major component will also miss the planned launch, namely the dashboard update itself. Major Nelson tweeted the news, noting, "the timing for the Xbox 360 dashboard update has been slightly delayed." Concerned citizens will receive a status update "later today."
Given the last minute nature of the delay -- so last minute that it didn't halt this morning's press release announcing the rollout -- we can't yet say for sure whether it's a matter of hours or days.