Best of all, it doesn't suffer from my old Logitech G7's double-click problem. The G7's left button had been double-clicking on single clicks for a while now. It's a known issue and seems to be why that model's been discontinued.
The X8 has a USB cable that charges the mouse as well as acting as its connection to the computer. This cord attached magnetically to the mouse so it doesn't need to go in a socket with sliding connectors that can be broken. It also comes off without damaging anything if the mouse somehow gets moved too far.
Now I'm not usually much of a MicroSoft supporter, but this is a fine piece of hardware.