Whoohoo! Windows backup is there. Proeminently:
They also mention the Shadow Copy (aka Previous Versions). This is a standard feature now in Windows Server 2003, which is invaluable for many many customers. Now we are bring it to the masses directly into Vista.
Did you delete a file by mistake? Or did you overwrite it and lost your old work? Just right-click on it (or on the parent directory) and you will see all its previous versions in the last month.