I'm 16, but I often feel out of place and a bit too old around the majority of people on Minecraft servers, even sometimes people my own age. Online I'm usually hanging about in communities with a slightly older audience (18-25) so I feel I kinda fit in better around people who are a bit older. I'm still a huge fan of the game, though. I've been playing since early 2011. I'd love to join a server and play with some people who are slightly older and more mature than the average player as well, but If you honestly consider yourself mature and you're young, I'm perfectly happy playing with you too!
My Skype's [redacted] if anyone's interested. Just send me a request saying you come from the Minecraft Forums
Hope to play with you all!