Yesterday there was this meeting in Rotterdam. It proved to me again how powerfull such meetings are.. I was very happy to meet Erik Zachte. Erik has earned himself a great reputation for the statistics that we provide with our projects, I learned that the Wikipedia and the Wiktionary statistics are based on similar data but they are slightly different in their presentation.
The biggest improvement for the production of statistics has been the policy that the dumps of the Wikimedia Foundation are in a XML format. This provides a much more stable basis for the production of statistics. With the advent of Wikidata and single login, I worry about how this will affect these popular statistics.
It was great to have Erik reassure me that we will cross that bridge when we meet it, "because we have always done that". Issues that may arise are: currently we do not have Wikimedia wide statistics, with single login implemented we can. Wikidata projects will be .. where and will probably not count for the project that the data has been entered for. With the introduction of the namespace manager in Mediawiki 1.6, some of the assumption in the statistics may have to be revisited..