I knew the following members before they joined: Raven1073 (best friend during high school), Calliope (best friend during high school and beyond), driftwood (best friend from high school - pruned), Mum (Mum - pruned), ms_devli (cousin), Tweety_ch1ck (sister), Nandor (best friend from high school - pruned) and Loony JosH (stepbrother).
I've met the following members after they joined: Jewels, Sakura Yume, Rinoabella, Wyllius, ~Tenderness~, ShlupQuack, ButThePoncho, Cid, Sean's Wife, Nino Brown, TheAbominatrix, Etienne, Hanbun Heiken, Miriamel, The Man, Kyono, Squally Leonharty, Lenna, Thingfish.
Of those I've met after they joined, I'd say that I know Lenna irl, since she lived with me for a few months.
I'll likely be meeting smittenkitten, Shauna, boris no no and Chaos this year (as well as others, but for those four it'll be the first time).
Hope I didn't forget anyone. =x