To add to the above: This is taken straight out of JD2020 so let's put a rest to the timing of the release of the map pack.
FS is available on Xbox 360 TONIGHT, at 2AM-ish PST (it may take time to propagate).
This means the DLC will be available on these cities/chk time zones (01 Feb / Tue):
2:00am - San Francisco/LA
4:00am - Chicago/Houston
5:00am - NY/Miami/Toronto
11:00pm - Auckland