Windows 7 Service Pack 1 is now available from Microsoft's Website for download, or via Windows Update, and by ordering an installation DVD. Windows 7 SP1 takes roughly 30 minutes to install, and you'll have to restart the computer halfway through.
The recommended (and easiest) way to get SP1 is to turn on automatic updating in Windows Update in Control Panel, and wait for Windows 7 to notify you that SP1 is ready to install. It takes about 30 minutes to install, and you'll need to restart your computer about halfway through the installation.
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