1. Command and comfort - the network controls everything from the heated seats to the remote starter. 2. Many devices ("nodes") are present on this network and communicate interesting metrics to each other (which can be viewed relatively easily). 3. You can not only view data on the network, but you can send to the network. Using tools like libVoyager, developers can design software that executes commands (lock doors, unlock doors, engage the factory remote starter, turn on/off the heated seats, etc). So with a little imagination you can see why they are so popular.
What these adaptors do not do: 1. No OBD. They can't be used with your favorite OBD software... Not yet at least. 2. You shouldn't leave it plugged in while driving since they are still just prototypes, which means they could have bugs. 3. there is little or no software that utilizes the adapters yet. You basically have to be a developer that's doing your own testing. The adapter will get you connected with the Single-wire network but it's up to you how you harness that power :)
Sleuth (Android SWCAN App) is available on GitHub (open source) and currently has lock and unlock buttons as an example of how to use libVoyager. So if you're and Android programmer, that's where you may want to get started.
So if you want one for your own testing (remember no software really supports them yet), please contact me at gmail.com, GTOSoft @