I just got my surface and right out of the box it wouldn't let me update any of the 15 app updates that it said I needed. I tried going through the settings to do the windows update and received another error saying it couldn't update. It sent me to Microsoft support links that were complete unhelpful. Shut down/restarted a couple times with no change.
The next morning I went through the desktop to control panel and updates. It listed about four or five critical updates that had failed and pupped up saying that I had outstanding windows updates. I told it to update through the desktop and it finally started to update to 8.1. 2 hours later I was at 28 of 38 updates before I had to head to work. I have high hopes for when I return. I hope that this will allow me to update the pre-installed apps and download new ones.
This is extremely frustrating to deal with right out of the box, especially since my wife is anti windows 8 and told me it was a mistake to get the surface. She was pretty heavy with the "I told you so's."