@cory.surber,
The Hue Hub REST API supports a call to supply a list of all the bulbs in the system with their room hierarchy plus their current consumption. Sense polls the Hub regularly to look for updates / changes. But the thing that is unique about the Hue Hub, vs. a smart switch based system is that the Hue knows about the status and power characteristics of every single bulb. Hue has each and every model of bulb characterized for consumption vs. dimming level.