Okay, I did vote 15-16, but since C&C and WOT have grumpy old guys and K2-pits have scary pre-teens, the average is going to be around 20, 23 probably. Most of the fora denizen is composed of teen SW geeks and folks whose first platform was probably Xbox and pap's PC, while the really active people seem to be quite a bit older.
I think it's frankly quite daft to think that's most forum members are in their twenties. We have a wide range of ages here, some would say wider than usual, since SW-mania knows no age bounds. Yes, not everyone is an SW-geek(thankfully), but over half of the members did register thanks to Project Delaware. And those folks either write crazily immature, or are what the society calls 'kids'.