Thanks for the heads up! I got lucky though. It looks like my Surface RT installed this update, but I just happened to open the store during the 8.1 update and saw it was downloading it! I thought perhaps I had somehow touched the ad to upgrade, but know I know I did not. But I did about have a panic attack when I saw this happening. I wasn't able to cancel the download so I just closed the store app completely and opened task manager to make sure it was gone. When I re-opened it I briefly saw it again, but when I right-clicked it and hit cancel it said there was no install was in progress and it went away. I wonder if it's going to try the "upgrade" again at some point? So far it hasn't.
Either way this is incredibly annoying.
This is more than annoying. It is maddening!