Another major difference is that Palm's dock uses magnets to line up and secure the handset, and LG's accessory relies solely on the friction between a rubber ring and the glass back of Google's flagship phone.
It does shed light on why HP is suddenly adding not quite an iPod dock, but an iPod dock holder to its Pavilion line, although it seems like very strange timing considering Apple isn't selling docks standard with any of its iPod models anymore.