MMOs might just improve your language skills. The scientists subjected a group of Swedish students aged 10 and 11 to English language tests to examine the relationship of digital games and English ability, gender, and learning motivation. They found that regularly playing online games and MMOs in particular correlates with having a stronger English vocabulary. Yay us!
They also found differences between the genders, though the paper's abstract attributes that to its male subjects' heavier gaming schedules vs. its female subjects' preference for social media activities.
I can't be alone in having MMO guildies whose first language isn't English, and having seen their language skills improve dramatically over the years the more they type and interact with native speakers, I bet I'm not alone in not being surprised, either.