Just announced today by Microsoft on the Windows blog
Today, we reach our next milestone as the first major update to Windows 10 is now available* for PCs and tablets. With this update, there are improvements in all aspects of the platform and experience, including thousands of partners updating their device drivers and applications for great Windows 10 compatibility. Windows 10 also starts rolling out to Xbox One today and select mobile phones soon.
*If already running Windows 10, you will receive the November update according to your Windows Update settings. If you’re running Windows 7 or Windows 8.1, you can take advantage of the free upgrade offer and receive the November update as part of your Windows 10 upgrade.
My own personal notes.
You do not have to rush out to get it. Do so when you are ready.
This is an optional update thru Windows Update.
Though if you already have a older version of Windows 10 you should really get this release build.