When you have statistics about your website, you know about your public. At this moment in time, the Wikimedia Foundation does not invest in resources for statistics. Yesterday, some people announced "AOL-day"; it reflects the astonishing growth of the Wikipedia project. We are able to notice these things through the services of Alexa.com. When you look at the data, you find the distribution of the traffic to the different wikipedias.
As astonishing as the growth of Wikipedia is the apparent popularity of Wiktionary. According to Alexa Wiktionary is more popular than dictionary projects that have much more content. This is probably the effect that the association with Wikipedia brings us.
When you look at the traffic details for Wiktionary, the thing that strikes me most is the popularity of the Russian wiktionary. Such details points to the apparant strength of this project or to the need for Russian content. For me, this is relevant because it could be one reason why we concentrate resources on a given language.
As WiktionaryZ is a true Wiki project, there is no need to concentrate to much about the user interface. People WILL find what works and what does not work and to a large extend the user interface will evolve. However, at this moment we are thinking about the infrastructure of the project.
In the current infrastructure a resource is indicated by preceding the project name with the ISO-639 code; the Dutch wiktionary is therefore http://nl.wiktionary.org. For WiktionaryZ we do not have a separate database for each project. When we maintain this link into the mainpage for a language, we benefit in two ways; there is a main page for the whole project, there is a localised entry level per language and the statistics of Alexa remain relevant for some basic analysis of the demand of our project.