The new Raspberry Pi touchscreen can be powered via an external power supply or via PWR OUT GPIO connector on the Raspberry Pi and connects to the Raspberry Pi via DSI (Display Serial Interface) port. This also means that you can now run two displays via Raspberry Pi, touchscreen via DSI and one via HDMI, allowing users to use the touchscreen as an input device, which means that there is no need for a keyboard and mouse.
Currently, the Raspberry Pi touchscreen needs some assembly but later versions will be fully assembled. There are already plenty of stands and cases for the touchscreen in case you want to intergrate it with the Raspberry Pi computer.
As noted, the new Raspberry Pi touchscreen is already available with a price set at US $60 in the US and £48 in the UK.