Space for Color

When you take a picture with a digital camera, the sensor records the light and writes a file to the memory card. Digital cameras commonly provide for three ways of determining how the colors the sensor captures will be written to the file. These methods are vague and misunderstood and poorly explained in the manuals. Luckily, they don't matter much if you treat your camera like you should.

The image your sensor records is pretty ugly. It becomes a prettier looking image when software processes it into a final form. There are multiple ways to make that translation. Your camera has software that can do that with two options: Adobe RGB and sRGB.

The completely useless description in the Fuji X100s manual.
What those two settings do is translate the RAW image into a pretty JPEG by selecting a range of colors from within the gamut of colors captured by the sensor. That's what the "color space" is, and Adobe RGB and sRGB handle them differently.

If you are shooting JPEGs and letting the camera do the processing work, then the choice of Adobe RGB or sRGB can matter, and there are several great websites explaining the differences and consequences. 

If, however, you are engaging in photography as a creative pursuit, then you understand that developing the image is an extremely important part of the creative process and shouldn't be left to the automation of a camera. Instead, you should be shooting RAW images and developing them yourself.

As quoted elsewhere on this blog, Cartier-Bresson wrote:
During the process of [developing], it is essential to re-create the values and mood of the time the picture was taken; or even to modify the print so as to bring it into line with the intentions of the photographer at the moment he shot it. It is necessary also to re-establish the balance which the eye is continually establishing between light and shadow. And it is for these reasons that the final act of creating in photography takes place in the darkroom. 
The Mind’s Eye, at 39. The creative process can't be completed if you allow the camera to do the work.

So, the only consideration of the color space you select in camera will be the naming convention allowed for the files (Adobe RGB often has an initial "_" character), the histogram, and any JPEGs generated along with the RAW file. Otherwise, shoot RAW and be in charge of the entire creative process.

The choice of Adobe RGB or sRGB properly only matters when you export the final image. At that point, Fuji is right: Adobe RGB for commercial printing or stock, and sRGB for anything else.