Is this really a "wiki" or is it an online document editor? It's easy to create the basics of a "wiki," and while reliably importing documents into a wiki isn't easy, it's just a starting point. The important features of a Wikipedia (Mediawiki) are an emphasis on links within the site, the ability to view changes across the site, changes on one page, and to see how a page was composed in clean markup, the clean markup also preventing behind the scenes jumbly messes of "structure." Missing any of these points loses a vital aspect of wikis. The category structure and templates are also important features, supporting what in Wikipedia's case is a strong support community that can go well beyond what a formulated menu structure can offer. (Mediawiki has emphatically refused to implement any kind of fine grained access model, this is one area other wikis have advantages.)

But now people expect more, they don't want to be forced to use markup and they want to simultaneously edit documents in a rich editor, in a social setting where its easy to find and connect with other contributors. This is the current focus of Wikipedia and while other efforts have their own strengths, not connecting finely to Wikipedia's developments is, to me anyway, missing the greatest element of development.