[jarofgreen]

From my experience as an event organiser, there are some ppl who just won't come if you do that.

We run a popular Meetup that does introductions. You can say lots or you can just say "I'm james and I'm here For The free drink." And even with that easy out, there are still occasionly ppl who don't want to say a single word and wont.

You can try and set the tone that everyone can contribute. The moderator can say things like "does anyone who hasn't spoken yet Want to add anything?". Rounds and moderators calling on ppl is good to.

I wouldn't like to try actually forcing tho.