I don't know what methodology is being used for distributing it this way, but SP1 was available for me this morning on Windows Update. I have made no modifications to anything, so this is definitely the real deal.

My brother has 32-bit, and did not have the option of SP1. Could be only in the offing for x64 systems at this point. I don't know.

In any case, I expect your wait is very short if you have any wait left. Please consider that before downloading from questionable sources.