What (and where) is Yosemite's "dark mode"?

Open General preferences and check the box here:

System Preferences > General > check the box...use dark menu bar and Dock

Go to Preferences > General.

Right underneath appearance select "Dark Mode"

They should have called it black menu bar. That is all it is. A dark Menu bar with dark menus. OH - The dock goes dark too...

It has absolutely nothing to do with a dark mode... All apps are just as bright as they normally are and the black menus (The Dark Mode) is actually making those app windows appear even brighter than when in normal mode... The dark mode is thus in reality a "Make my App Windows Look MUCH brighter" Mode...

If they had made the apps go dark too, then it would have been dark mode... But this is a joke, IMO

The only actual purpose I can think of for dark mode is for folks who want the entire interface to have a consistent look when using pro apps from Adobe, Apple and other sources who all have the idea that a pro app should have a dark gray design. As if somehow that makes it work any differently. So as an example, this is how Premiere Pro looks under Mavericks:

Boy, that gray bar on top really bugs me. If only there were a way to make it a dark gray to match everything else. In Yosemite, now there is.

Otherwise, it's just for folks who like the Goth look, or whatever. But no matter how you want to look at it, it's a simple preference choice for the user who wants a bit of a different look. That's about all.

Well... Kurt is actually hitting on a good point... He is right... The dark mode is great for apps which are already dark !