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PCWorld article.
"With little fanfare, Microsoft Corp. has moved up the availability of Windows Vista Service Pack 1 (SP1) for TechNet and Microsoft Developer Network subscribers, saying they will be able to download the update by Friday at the latest.
It was the second time in three days that Microsoft changed the release of the release-to-manufacturing (RTM) version of Vista SP1 for the IT professionals and developers who pay hundreds of dollars annually for the right to download and test software before it's offered to the general public."