I would say under 100, Peter.

49

About 10-20.

I'd say 500 to 1000 post regularly, but about 200 are "active" and comment and read here.

Haven't a clue. But it's a whole lot less than the number of members.

27

There are more "members" than I would care to count and most of them are not "active".  I would consider someone being active if they are posting regularly (at least once per week), commenting on posts or interacting in the Q & A.  There are lots of ways to stay Active in the Rain!

77

I would say i about 20 names i see daily and perhaps 50 active. I wish there was not those couple of people who "hog" up the blog roll with robo posting so it would be easier to see other posts too

I'd look at those that blog and/or come to the Q&A regularly, with the exclusion of the robo bloggers and (maybe) people who soley do automated listing posts.

I'd say probably between 100 and 200.  The majority of the member roll is inactive.  If you have 1200 points and have been a member for more than two months, you're inactive.

Nine.  There are nine active members.

I would not say top 50 in any state. Someone figured this out once & I can't remember who. 

I’d guess 20,000 +-

Like you said, first challenge is defining "active".
After that, not sure that there is any way for members to determine the hard numbers. 
Personally, I'd put that number of semi-regular folks (Q&A, commenters, bloggers) at somewhere between 1000 - 2000, and I could be overestimating.

Running through the Ambassador list, I'd say at most 25% of the roster is truly participating here.

Far and away if you go through the new members daily, MOST of them are strictly here as a directory entry and not here to participate.

Not sure how to gage that Peter. The leaderboard may be a place to look.

I am in the Q&A almost daily. 

Posting blogs - rarely ever these days. 

40-50.  Somedays, I have a tough time finding 20 posts to comment on...A

the top 50 in ga are not active.  I'm not really.  A lurker.

Let us know if you can count them.

Make sure you have Facebook connections. That is where you will find many of the inactive members as well as active members.

It can't be many. I live in NY and watch my points rise slowly- and I am in the top 75 for NY State and Top 10 in Manhattan. It seems I am the only one actively contributing on a regular basis so my rise in ranking is only limited by the amount of time I want to invest here. I enjoy writing and contributing so for me that is a better use of my time than any ranking would convey. 

1,734

Over 300,000 people on the list and less than 1,000 participants!

100 active in the US

half dozen in our state.

Activerain is not as relevant as it used to be. What makes me say that? I am #97 in California (where I used to be like #300 something working my way up slowly) and #1 in Monterey County and Carmel-by-the-Sea (where there are no other agents competing on Activerain and where there are some tremendous agents that I am working/competing with daily.

Conclusion: I just can't spend a whole lot of time on AR anymore in order to compete in my marketplace--as much as I might like to.