The best thing I like about it, at least for now, is its simplicity of use; as long as you know how things work there's no problems with using this product! There are some features which can be improved in order make them more useful (like adding tags when you add pictures).
It doesn't have any downsides so far though. Maybe if we could improve user experience by letting us do everything without having to ask help from an expert every time would be great but not sure what kind of development will solve such problem since tabs are used everywhere around web nowadays - even Google Chrome has tab feature implemented :D.