The DMC-GX1 has a large, high-resolution LCD but Panasonic made Live View Finder (DMW-LVF2) for finder-enthusiasts. The DMW-LVF2 displays the same information as the LCD when you equip the DMC-GX1 with it. It is effectively used in situations where the LCD is difficult to see, such as under bright sunlight. And it is also handy for low-angle shots because it can be tilted vertically from 0 to 90 degrees.
* The DMW-LVF2 must be attached to the hot shoe of the DMC-GX1, so it cannot be used in combination with an external flash.