EU server here, and I just got 5143 XP(while wearing the hat) on my lvl13 new mech kitty, made the cute little thing ding lvl17.
Seems like its back to the old leveling ways again.
Oh and if you want to level two pets at once, go with Spawn of Onyxia breed id 4, if you have it. Really easy to solo Farmer Nishi, just make sure your low level pets can take one hit from the sunflower aoe.
Edit: I did the same battle again, only this time with a lvl19 and a lvl14, they only got 2058 XP + 2601 XP and my main battle pet died(intentionally) both times. Does a lvl19 really get that much reduction compared to a lvl14? (rhetorical question, yes it does