People worry about privacy issues of Facebook and Google, but Wikipedia, being the nice and not-for-profit guys that they really are, does not receive much attention. However, if access logs are not properly taken care of, they could be mined and exploited by third parties.
When a visitor requests or reads a page, or sends email to a Wikimedia server, no more information is collected than is typically collected by web sites. The Wikimedia Foundation may keep raw logs of such transactions, but these will not be published or used to track legitimate users.
The words 'typically' and 'may' are weasel and raise some questions. For example, what is logged? IP, browser version and OS are typical, is it also logged, as in the edits? For how long is it kept?
It's true that
Wikimedia policy does not permit distribution of personally identifiable information under any circumstances.
But it made me wonder that since selected editors have privileged access to that information it may only take one human error or evil intent to leak it.