Microsoft will be released today 8.1 Windows Update via Windows Update. If you're in a hurry and can not wait, the company has silently download links for all the files required to install the new version.
As you can see in the list below, Microsoft has released the download links for all versions of Windows 8.1 Update. Installers are included for Appliances 32 and 64bit, but also for ARM tablets, like Microsoft's Surface.
If you do not know the order in which you will need to install the files you download, KB2919355 is the main package, so if you are running a fully updated Windows 8.1 system, this is the only package you need to download.
Download updates for Window 8.1 Update x86:
KB2919355
KB2919442
KB2932046
KB2937592
KB2938439
KB2949621-v2 (only for Window Server & Hosting 2012 R2)
Download updates for Windows 8.1 Update x64:
KB2919355
KB2919442
KB2932046
KB2937592
KB2938439
KB2949621-v2 (Windows Server 2012 R2 only)
Download updates for Window 8.1 Update ARM:
KB2919355
KB2919442
KB2932046
KB2937592
KB2938439
