Direct Download for Revit 2014 Update Release 1:
The Live Updater from in-program uses mshta.exe to download and execute the file.
On Windows 7 64 bit, you might be able to prompt the download page by opening:
Also, after using Comm Center, you will find a HTA in this folder that you can run:
C:\Users\USERNAME\AppData\Local\Autodesk, Inc\Autodesk Revit\20130308_1515(x64)
Heads-up via tweet from Steve Stafford:
If you let Revit's Comm Center access Autodesk you'll find that there is a Web Update release 1 for 2014 now. Heard already? As you were...
— Steve Stafford (@Steve_Stafford) July 18, 2013