As you stand in Dalaran ” I think I broke it” broadcasts itself in stereo – Blizzard developers surely would have perfected the art of pet noises, and actions by now – I mean XT would only be the most annoying pet of all time for a purpose.
What purpose? – It’s a brilliant marketing tactic.
Forget the shiny pony’s that run past you in the main street looking like horses with chicken wings attached. They become as dismissible as every person riding on a Raven lord or spectral tiger. It’s just another mount in the myriad available.
Lil Xt isn’t so easy to dismiss. He is noisy – loud – you don’t need to be looking at him to know he is there,
and how is this a marketing strategy?
Your thinking about Lil XT. Every time you hear him. Stereo. Why is he different to the other pets – that his voice is almost an announcement on a PA system. It’s so everyone knows he is there, and you knowing he is there means your thinking more about him, and your thinking how much you want him, and how cool it is that he can touch his toes, and makes so many loud noises.
Just a theory
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Pugnacious Priest's Warcraft Blog 
Yeah I passed on the Lil’ XT for now.
I bought the pony though…
Even I am thinking about the pony, though I do not like the look on the ground.
Must not think of pony!
Pony is the ultimate alt toy.
Cross faction and cross server, waiting for your alt to be made.
Oh… FOR PONY!
Stupid little brat always breaks his promise to not break them.
He needs a Tonka Truck.. ( couldnt break them with a sledgehammer) though it might have been a Aussie kids grow up toy..
Hence why I love those nice add-on people who promptly put together the Lil XT silencer. Like the voice wasn’t annoying enough when fighting–at least then I got the satisfaction of killing it!
If that really was their strategy, I don’t think it’s working very well. Maybe it makes some people want to buy it, but I’ve counted more “that’s really annoying” reactions than “that’s cool” reactions.