Except no, no one knows. Try again, troll.
Finding information nowadays is a very rare skill.
"I was speaking with GM today about this pet, he told me something like this:
"The summer pets will spawn at the 1st of june, so they are little different to the summer fishs :)"
So 1st of june is now CONFIRMED date.
Edit: Image for you: http://img96.imageshack.us/img96/4863/wowscrnshot032013210526.jpg"
Also other comments point to twitter conversation with one of the developers.
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