The advantage of the new standard is that USB-C isn't owned by any one company. That means anyone can make them for cheap. The disadvantage: They might wreak havoc.
But the new USB-C cords are capable of supplying way more power to a gadget than micro-USB. If you charge your smartphone by plugging your USB-C cord into your laptop, a faulty cord could drain far more power from your laptop than your computer is designed to supply, destroying it -- and your smartphone -- in an instant.
The cords are supposed to recognize what kind of device they're sucking power from. If the USB-C cord senses it's plugged into a wall socket, it should crank up the juice. If it's plugged into a laptop, it should sip power.