In the meantime, lets look at some images I have taken. It is a tall order to get decent pics from the Shard because of the ever present reflections. Aim to go at the end of a day to catch some daylight, hopefully a nice sunset and then the city at night. Once up there, you can stay as long as you want!
This is the open air gallery at the top of the Shard. Don't worry, the glass everywhere is taller than you are. Just saying.
What more could you want :)