Microsoft's Mike Ybarra, Director of Program Management for Xbox, has shared the contents of what will be the latest update for the Xbox One console via Xbox Wire.
A few updates that will begin to rollout to Xbox One's Preview program include the ability for you to see who's in a party before joining, bring up a Gamerscore Leaderboard accessible through the Achievements section of your profile, and re-arrange pins on Xbox One home.
The Activity Feed will now inform you of any new items more clearly too. If one of your friends is broadcasting a game live on Twitch, you can now watch it easily through Game Hubs or the game title. You'll even be given suggestions on who to friend given your current friends list and your most-played games. Better yet, you'll be able to re-enable the ability to hide content like trials and apps you don't want to install.
As for the Xbox Beta app (and on console), the newly-integrated Avatar Store can be accessed though the Store through the Xbox Avatars app. You'll see more news information on trending topics and you'll see more friend recommendations as well. The Xbox Beta app also comes with a Compact mode so that you can switch between tabs more easily.