Various personal VTOL has been proposed for decades but unfortunatelly, never be successful. The biggest problem is safety concern against power fail. When power is failed, VTOL will immediately fall like a stone. Imagine you are diving from concrete wall on a bicycle with some 100lbs of stuff strapped on your back. Even from altitude only 10ft, it will hurt you pretty much.
Airplane can glide (unless wing came off). Helicoper can auto-rotate (give spin to roter like windmill, reducing decent rate by drag). No such power-failure safe landing method is built in with thurst-lift VTOL. Some designer tried to give redundency with multiple engines, but this option will reduce already scarce payload capability.
We'll need near-100% reliable power source, or some genious method of soft landing on power fail. I think if parachute can be launched and blossomed with exprosive (or compressed gas) so it can be deployd from low altitude...
Replay available now: A handful of emerging network technologies are competing to be the preferred wide-area connection for the Internet of Things. All claim lower costs and power use than cellular but none have wide deployment yet. Listen in as proponents of leading contenders make their case to be the metro or national IoT network of the future. Rick Merritt, EE Times Silicon Valley Bureau Chief, moderators this discussion. Join in and ask his guests questions.