And here's the proof!
I spotted Kaynor showing off his Hydra in Ironforge yesterday and couldn't resist bringing mine out as well. Sassy seemed pleased to finally encounter another of her kind. :)
This brings up the count of Hunters on Sen'jin who I know who have Hydras to...2.5. I know Gunwright had one but I'm not sure if he still has it or not, and so far I haven't run into any Hordies with em. That might just be because I don't visit Orgrimmar too often, though.
It's a fun feeling, seeing someone else with the same rare pet--I imagine it's a little like how a Hunter with a ghost wolf might feel seeing another one, though the Hydras were much easier to tame (the tricky part being simply leveling quickly and getting a specific daily). For a while, I thought I was the only one here with a Hydra--now I know I'm not, and it's not so lonely, more like being part of an exclusive club.
The Azerothian Hydra Fanciers Association perhaps?