Maybe Lou has had time to do enable logging. Perhaps we'll find out who it is this time.
The problem with logging is the space it takes up. I used to run a server which had logging and backups so you could go to an area, see who changed what recently and you could revert any changes. The problem was it used up multiple GB's of space in just a couple of days. Eventually it filled up all the HDD space on my server and corrupted the world because the world save couldn't save properly. (luckily I had offline backups!)
This was at least a year or 2 ago though so maybe there are better solutions now.