During the Community Council meeting yesterday we were talking about the general health and excitement levels of the community, and whether we were loosing a lot of members. I had a vague memory of us (Canonical) having an internal graph of number of members on the ~ubuntumember team, and I dug it up to see what story it told. As it turns out, it's a very positive and healthy one \o/
Here's the graph of number of Ubuntu members over time (there's no data prior to Sept 2007):
Note that the curve starts to really go up around May of 2008, that's when the membership boards took over member approvals from the Community Council.