Microsoft have released Windows 7 Service Pack 1! The size may range from 78MB (if you update frequently) to 1050MB (if your Windows is at dinosaur’s age). There’s a manual download version available at here. Well, obviously they want you to use Windows Update since the manual update size is at multifold.
Description from Microsoft:
Windows 7 Service Pack 1 (SP1) is an important update that includes previously released security, performance, and stability updates for Windows 7. SP1 also includes new improvements to features and services in Windows 7, such as improved reliability when connecting to HDMI audio devices, printing using the XPS Viewer, and restoring previous folders in Windows Explorer after restarting.
Source
Judging from the description, they might have slip-streamed Windows Activation Technologies update KB971033 into Service Pack 1. So, if you are using a pirated version of Windows 7, wait for the green light or update at your own risk.

I was expecting a better caption rather than a dull note!
Windows: Congratulations! You have installed Windows 7 Service Pack 1. How do you feel?
Me: It’s slo… <censored>
Windows: Thank you for being Microsoft’s customer!
Me: …
Right now…

My Computer Properties
Just in case you are wondering what is my response to this update, it slows down your PC. Good luck and good day.