The "settling" of the forum use hasn't been caused by the restructure, that I can say unreservedly.
The numbers indicate that the forum has been slowing since Nov/Dec and appear to have settled into a regular pattern during the last 2-3 months.
We're still growing by...
* 150 to 200 members a month
* 200-odd new topics per month
* 1500 to 2000 new posts per month
... and we still peak at between 20-40 people online at one time daily.
Personally, I think the community around here has been slowing as people invest more time and dedication into mods and projects that are actually moving forward (instead of just getting to the planning stage and dying), or have settled into other tasks outside of conversing in the forums.
But thats just my own viewpoint.