Currently IIS has 18,358 registered users (unique user IDs). I have trolled through the entire alphabet listing, looking at join dates and activity (posts). A very large number seem to have zero posts - perhaps they are just readers, hard to know. Then there is another large group with single figure posts. A very small percentage make it into the hundreds and thousands of posts, and I suspect these members are responsible for most of the activity on the IIS Forum.
I am not making any judgements about membership, other than the heavy hitters are the backbone of the community, and can usually be found in any thread where a question is asked.
So thank you to all the heavy hitters for your active participation.