That is certainly a nice idea. I've done a minor update to my Stats mod which adds some more extra info, like how many users that have made posts the last week and month, how many users have each rating, how many users that have each title. Also some info on total number of characters in the database as well as a average of characters per post for the whole forum as well as each board. I will write up instructions for this in the near future.
A mod with graphs for stuff in each month would certainly be nice. I guess the information should be gathered and saved once each day or something, since the calculations could become quite heavy on the server.
Possibly I could write some thing up without the graphs and without any cache this week, but I'm not sure how much time I'll have. I've just started looking at integrating Horde/IMP with threads and it seems to be quite an undertaking...
