I believe that Runescape should NOT be for only 13+, but instead, 7+.
Runescape, is a intriguing game. For people 10 years old and less, it is one of the most immersible experiences possible for youngster to experience. I say this from personal experience. I started when I was 7. Every day after School, I bounced on my heels, excited to once again delve into Runescape.
Runescape's game world is large, and defiantly a lot more interesting then taking a stroll around your neighborhood. By playing Runescape, younger people will also gain a learning experience in creativity. Runescape really jumps up the creativity of one, and will also open them to a lot more genres, fiction and non-fiction, in reading and watching [TV]. If it wasn't for Runescape, I perhaps wouldn't be the anime fanatic and fantasy novelist I am today.