Note: Pet is on Papa Hummel's Old-Fashioned Pet Biscuits; actual size of the pet is smaller.
Thanks to El's Extreme Anglin', the Sea Pony pet was confirmed as a fishing drop from open-water fishing on Darkmoon Island. The new zone requires a fishing skill of 75 for non-junk catches. With this knowledge in hand, I set out on the PTR to catch the Giant Sewer Rat version 2.0 lol.
About an hour and a half and 190ish fish later, Sea Pony! I took some video of what it looks like since the summoning for this companion's pretty unique. Not in the video: The Sea Pony flies alongside its owner.
I don't know if it's the name of the pet, it's large jewel-like eyes, or the little squeal vocalizations it makes when you click on it, but I find this pet absolutely adorable. :) It's just the sweetest little thing; I can't wait to fish and fish and fish for this companion in the next patch!
PS: I'm REALLY grateful that there's an area where you can fish for it that's considered sanctuary. I'd rather not fear for my life while trying to fish for hours on end for the Sea Pony. So thanks to the developers for this one!