Fair enough, but I feel like it's kinda weird that the option is there in plain sight, if it doesn't map by default.
@Sebastian Parborg (zeddb) you seem knowledgeable, can I ask you how I do map the smoke color attribute to the color?

I could just change the shader color, but that changes all smoke in the domain to a monochrome color. I want to have multiple objects emitting different colors, and do stuff like keymapping the emitted color to make cool effects.
(If this is not a suitable place to ask this, then I apologize, and would love being pointed to the right place to ask.)

In the domain shader, simply type in color in the Color Attribute slot

I'm a little confused. Does this mean that in Blender 2.8, we can no longer animate the smoke color to change as it's emitted while using Cycles as the renderer?

I was following along with a smoke tutorial here but in 2.8, the smoke no longer renders using the expected colors. As @Kobe Reygel (Arkay) mentioned, changing the shader color changes the smoke wholesale. Is there another way to do this in 2.8 that will still allow me to animate smoke colors from a single emitter?

@Chris Camargo (chriscamargo) you can! Like Sebastian said above, go to the smoke domain, go to its shader nodes, and type "color" in the box called "Color Attribute"

After doing this, the smoke behaved like it did in 2.79 again. (and thus being keymappable)

Apologies, I didn't make the connection initially. Thank you, @Kobe Reygel (Arkay) and @Sebastian Parborg (zeddb), that did the trick!

To animate the whole domain is not what is asked for. the emitter effect is something amazing different in Cycles where the emitting item can have changing color.

Since Blender 2.80 "Smoke color" doesn't seams to work anymore (Cycles) for renders and animation… It appears grey in Cycles renders. Does someone here has the solution to fixe this ? I tried this way, using Nodes, but it changes the entire color of the smoke (right side of the video).