Not quite. Being like a normal meeting is exactly why this is not an effective brainstorming session. Normal meetings usually revolve around everything (critical analysis, evaluation, decision making, agreement, judgment and blame) but creative play. It is often very tempting to fall back onto the comfortable routines instead of breaking out into a different way of thinking.

Correct. Unlike normal meetings, brainstorming sessions must necessarily be less bound by status quo hierarchies, policies or even a lot of political correctness and social decorum. It is perfectly ok to interrupt for example. By reducing these social shackles, we can encourage more ideas to flow freely.

Correct. We can only be creative when we are comfortable and safe - both physically and emotionally. When we start trying to judge whether an idea is sound or wise before we express it, the session will quickly deteriorate into silence. The more unusual the idea, the greater the potential for radical innovation.

Incorrect. Silly ideas are often the ones that really break the mould and fundamentally change entire industries. The session is not working if the participants are not going with the flow and building on ideas, however absurd it may seem.

Yes. These are all signs of a brainstorming session that is going very well. Good body language (relaxed, open, happy, light) and a good flow of thinking on top of each other are good things.

No. "Being silly" is a form of premature judgment. And this will stifle flow and cause participants to start holding back and watching what they say. Many breakthrough ideas are often "silly" when they are first proposed.

Not good! The session is becoming too fractured. Ideas need to be built on to flesh them out a bit more. Otherwise they can be hard to evaluate in the next phase. The more you build on an idea, the more its potential is revealed.

Correct. There are many reasons why this could occur. Maybe it's getting close to lunch time? Maybe the participants all have strong egos, and are drive by the need to have "their" idea heard.

Not correct! Brainstorming sessions are about the exploration of possibilities, and not the imparting or learning of knowledge. The facilitator is better off telling stories that will stimulate further ideas.

That's right. As a facilitator, you have multiple roles to play. Taking over the session as your personal platform unfortunately is not one of them. :) You need a balance between contributing to the ideas pool, but not vesting too much in getting "your" ideas heard or accepted.