It’s cool to see such great design things coming out of Facebook. Is this what they’ve hired all those designers for? Could be, but I really like it!
This design is rather minimal which is perfect for this scenario, the grid is also nice how it goes from large to small as you scan down the page and also becomes very focused. The colors are minimal with basically just blue and gray which fits perfectly with other things Facebook has put out in the past. Overall this is a superbly executed looking design with one purpose and everything designed for that one purpose of sharing a story.