The pitch of the G19 is that it will help you "stay informed while you game". In practice, that means an LED panel at the top of the keyboard.
Without a game running, the display cycles through various options, such as YouTube, CPU performance and so forth. Launch a game, and the display switches to show health and ammo for an FPS, or other appropriate data.
12 function keys to the right can be assigned to shortcuts, macros, scripts and other functions. There's a macro manager and a script editor to fine tune. You can also change backlight colour through a full RGB selection of colours.
If you want your WoW gaming in green backlight with one set of macros, but your Crysis gaming to be backlit in red with a second set of macros - that's entirely configurable.
The windows key disable is a nice touch, too, and saves you prising off those command keys. The keyboard itself is reassuringly sturdy, with excellent responsiveness. It's an impressive gamer's control hub.