(Sorry for the cross posting, but there are several groups who might find this interesting.)
For years now, it has been common for people to claim that "all the good editors are jumping ship" or "we are losing our best people". Generally, this has not proven to be true: people come and go, to be sure, but as some people drift away, others have drifted in. Whether the rate of burnout is "too high" or "too low" or "just right" is quite hard to say.
However, it ought to be possible to at least quantify what that rate actually is, by using the Erik Zachte statistics or a modification of them.
I would be fascinated if we could figure out such statistics as
"For any given edit, what is the average length of service of the editor?" "For any given edit, what is the median length of service of the editor?" These could be measured by either time since first edit, or total number of edits or (perhaps best) some weighted average of the edit history.
It would be nice to track that number over time... are we becoming "younger" as a community, "older" as a community? Staying about the same? Are old-timers sticking around longer than they used to, or jumping ship faster?
There are also a whole set of related questions around newbies:
Are newbies more likely to stick around, or less likely to stick around, than they were a year ago. Some people feel we are being overrun by newbies, others feel that we are becoming a more closed and cliqueish community which does not welcome newbies.
I would measure this by saying "Of people who made at least 100 edits a month ago, how many of them made at least 100 edits this month". And similar stats for "at least 10 edits". (Merely looking at "new accounts" would not be right, because we had a huge spike in new account creation when it became necessary to have an account to create a new page.)
--Jimbo