Spot, the latest packbot from Boston Dynamics (owned by Google) is very impressive, and certainly robots of the future will have no problem negotiating tricky terrain:

A feature of MapMerge is a 3D mapping system that will allow robots to navigate cities. After watching Spot in action it could be argued that a 3D map isn’t needed – Spot will manage kerbs and stairs without a problem.

Three points on that:

1. There’s a big difference between wandering about and knowing where you are going. Existing 2D maps might not have everything spot needs to get from A to B.

2. Having 4 legs takes up space. Courier robots will need to be compact – for getting through tight spaces, fitting onto elevators, and generally not getting in the way of people. Two-wheeled robots, like the Segway, would be more suitable. And wheeled bots can’t (easily) climb stairs or even get over kerbs.

3. Batteries. Wheels are more efficient than legs, and for being useful over distances without the inconvenience of recharging, expect to get a better economic ratio from wheeled devices.