Not that this is news or anything, but it seems that when I created this group several months back, I also apparently started A Thing. Since then, there have been other groups started for celebrating ponies of particular colors. I've found five so far; if I've missed any, or if any new ones get founded, please let me know so I can add them to this list of links.

In alphabetical order:
Beautiful in Blue
Outrageous in Orange
Stunning in Silver / Gorgeous in Gray
Wonderful in White
Yerning in Yellow*

Join them, won't you?

*Should be "yearning", but whaddya gonna do?

While I'm pretty sure it's completely unrelated to any of these groups, it's worth mentioning that the super-talented fan artist Uotapo (DeviantArt gallery link, Derpibooru artist tag link) has done some art involving EqG versions of a few ponies sorted by color-coding:

Grayish Ponies
Bluish Night

If we're lucky, there'll be more.

4942363

Makes me wonder what happened to the other colors. Green, brown, red? Well, I guess maybe not red...

--Sweetie Belle

4942363
Nyahaha.

I have joined the white one. I really like white-coated ponies. So pretty and pure-looking.

D-does that make me racist?

4942581
Not a lot of green ponies? I mean, the only one I can think of off the top of my head is Merry May.

And while I'm sure there are brown ponies besides Time Turner, I don't think they're all that common among a species where bright pastels are the norm.

4942604
Nah -- preferences for pony coat colors isn't all that different from liking certain hair colors on humans. As far as I know, there's nothing racist about my fondness for redheads. Nor does it interfere with my appreciation for women who aren't redheads.

4942813 Umm...TreeHugger is green too

4942815
Okay, name four more. I don't think half a dozen is an unreasonable minimum for creating a group dedicated to green ponies...

4942833 Ms.Peachbottom

Lyra Heartstrings

Granny Smith

Apple Blossom

Green Jewel

The guard on the left