when you share a link and the pictures are fetched you can browse through them with the 2 arrow buttons to choose the right one.
http://screencast.com/t/gmpeLZFfRA
unfortunately the way it is right now these buttons are "jumping" up/down and right/left depending on the image sizes so it's really a pain to go through a bigger list of pictures as you always have to move the cursor to the new position of the button. also the use of keyboard control seems not to be implemented at this time, both things should be fixed in terms of better UX.