The video editor looks quite powerful with an attractive interface and plenty of tools and options to fine tune video creations before sharing them with family and friends.
Apparently you can only share directly to SkyDrive at the moment, though it's possible to then share that SkyDrive video anywhere you wish.
Take a look at the walkthrough below.
Xbox One Upload Studio Walkthrough:
Kye Lampe walks through editing a clip with Upload Studio, including uploading and sharing videos straight to SkyDrive from Xbox One.