Excellent thread �� one thing wp8 lacks is the my apps section like google play where you can see all apps together you own and which need updates...
Shortcomings...
unfortunately it shows all your downloaded Apps, even if you have deleted some of them. And most importantly it doesn't show any update notifications. But you do have a list there of your Apps and they link back to the store, so if you are loggedin you can go to them to see if there is an update.
Personally I think it's faster to just go to the Free/Most Popular App lists and go down them and check for updates there...what with the Store Live Tile 'update' functionality broken/intermittent <eyeroll>