So there is this guy name IWOVEHACKINGLOLOLOLOLOL, and he said that if you go to forums to register you can get a longer name, so I did, and it works, I typed in BuZeLightyear. Is this a bug or what?

Registering on the forums expands the amount of characters you can use for a username, although it is not an infinite amount.

This was a minor glitch that I think has been patched

Although yes, on the game accounts can have a character limit of 10 and accounts made on the forums can have a character limit of 15.