lord only knows what people are doing who have a limited internet either by bandwidth or consumption ie a low usage limited plan.
Since Win 8.0 I have had to leave the laptop 5 times over night plugged in by Ethernet cable to the router downloading updates. It must be over 3 G's of download. If you get a new Win8 out the box your a week and 5-6 reboots to get the unpdates required to go for win 8.1. They seem to stagger them, then when you eventually get the last one the free update will appear in the shop. You download that and then another 4-5 reboots worth of updates before you get up to this Win8.1 update.
Apparently you meant to check that the update has gone through by looking at the metro screen and if it has a power symbol and a search icon in the top right corner you have it.