I was getting nowhere on catalog.update.micrsoft.com with ie11 on windows 8.1 64-bit.
Looks like it was missing an active-x control (and doesn't prompt for it).
I used ie10 on another 64-bit machine (that I've previously used on the website) and grabbed MicrosoftUpdateCatalogWebControl.dll from %windir%sysWOW64 and copied it to the same location on my 8.1 box. Then ran regsvr32 MicrosoftUpdateCatalogWebControl.dll as an administrator in that directory and everything was peachy. Thought I'd share in case anyone else ran into this problem.
-T