It's not going to happen. Neo have said time and time again in the editorial that it won't happen because
A) Stress on the servers of millions of users changing their pets from EANESFOFOFOI to CookieMonsterIsBlue
B) Confusion to users
C) It'd involve changing the whole pet coding system to allow for things like changes to names when somebody is challenging that pet to a fight in the battledome
D) People would constantly want to change their pets names, making names available and unavailable constantly (See B for more)
E) Possible glitches that could occur (What if two people tried changing their pets names to the same thing at the same time ?), weird bugs that could occur from names being used of old pets
F) When you create or adopt the pet, you are accepting everything about that pet. If you don't want a pet with lots of numbers in it, don't adopt/create them with lots of numbers in them. You wouldn't like it if you Mum/Dad had the power to say "You know, I never really liked your name, so from now on, you're name is this..."
G) People would want the ability to change their user name after that (Repeat A-F with even more dire consequences)
G) They just don't want to do it, they've got more important things to do (Like plot prizes

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