I do not really have a favorite pet myself - but this is the one I currently have following my priest around all the time.
And the Chicken Rocket stays with my rogue for now. I may change the Rocket to the Fetish when I go raiding tonight.
Now that I think about it, on Feathermoon (a fairly large realm), I have not seen (or perhaps just not noticed) anyone else using the Fetish yet. Lots of companion pets all over Stormwind, but my priest Fetish appears to be the only one. It is kind of good to be temporarily unique at the moment!