Today during the Activision-Blizzard Q3 earnings call, Mike Morhaime finally revealed the percentage of revenue from the Moonkin Hatchling -- previously announced at BlizzCon -- that will be donated to charity.
As he said, it's the next companion pet for the Blizzard Store created specifically as a means of raising funds, and it will follow the same lines as the Pandaren Monk from last year, with 50% of revenue being donated. He also reiterated that the pet will go on sale in the store later this month.
While Morhaime didn't confirm that the proceeds will go to the Make-A-Wish Foundation, like the 1.1 million generated by the Pandaren Monk, it's probably a safe guess that it will be. Blizzard has very close ties to Make-A-Wish, and so these charity companion pets look to be another means to them contributing to the foundation.
Sadly there aren't any models available for the hatchling yet, so you'll have to wait on that a bit longer!