Kotaku readers have been writing in to that site, expanding on this decision and a similar one that has been handed down on the tactical shooter Counter-Strike. This ban technically applies to the whole country, as decisions made in one court system are technically the law of the land throughout Brazil. A reader noted that at the moment only the state of Goias is applying the ban, as other court leaders seem to think the decision may be flawed.
Fascinatingly, EverQuest isn't even commercially released in the country of Brazil. Even more interesting, reader comments seem to indicate this is a forced ban: copies of the game reported being 'taken' by the police. The ban (on EQ, anyway) seems to stem from the moral ambiguity of many of the quests:
As for EverQuest, Procon states that it "takes the gamer to complete moral conflict and 'heavy' psychological conflicts; for the tasks that are given to them could be bad or good. (...) Violent videogames that use violence are capable of forming agressive individuals, making it evident that is strong its influence on psyquism, reinforcing aggressive attitude against certain individuals and social groups".
Further commentary is available at Rock, Paper, Shotgun.