Microsoft is rolling out Windows 7 Service Pack 1 as an automatic update starting this week to anyone that hasn't yet installed the patch. The process is expected to take a couple of weeks at which time most legacy users should be up to date.

Service Pack 1 includes multiple fixes for flaws in addition to delivering several performance and stability tweaks. What's more, it will be a requirement if you wish to keep getting support for the foreseeable future so really there's no reason not to install it unless you have a very particular environment that can't be tampered with or your copy of Windows isn't genuine.

The move comes less than a month before Microsoft will end support for the original version of Windows 7 on April 9, 2013. Those running SP1 will see mainstream support run through January 13, 2015 with extended support carrying on until January 14, 2020. Under extended support, Microsoft will still issue security updates as usual but there won't be any other hotfixes, etc.

Alternately, users can elect to download and install Service Pack 1 on their own if one doesn't want to wait for Microsoft to do it automatically. If you go that route, you'll need around 1GB or so of free space for 64-bit installations and roughly 750MB for the 32-bit version.

You can check to see if automatic updates are turned on by visiting Start, All Programs, Windows Update. From there, click Change Settings in the left pane to see where you currently sit.