I have just reformatted and reinstalled Windows 7 Professional using a DVD that was purchased in January 2010. I have also accepted numerous Windows Update installations in the course of, I believe, 2 or 3 runs of Windows Update.
Last time I reinstalled (about 4 months ago), I believe I directly downloaded Service Pack 1 and installed it. This time I tried to see what Windows would recommend via Windows Update. I note that the Microsoft website says that Windows Update is the recommended way of obtaining SP1.
I am not being offered Windows 7 Service Pack 1 (KB976932). Does that mean I don't need it?