One thing that Wikispecies will not have is having a high reliance on
"vernacular names". Vernacular names are highly un-scientific with same
names covering many species, with many species without vernacular names,
with species being covered by many often regional names.
When Wikispecies is to interface from wikipedia, one obivous place to
put the links are the Taxoboxes. They would relate to the current
correct name for a taxon. This would imply that this should be a two-way
street. When Wikspecies decides that a name is not longer the currently
valid name; it would flag the taxobox as problematic.
The problem with one unified database is, that all users would find all
wikispecies data in the wikipedia space. But, WHICH wikipedia space?
Consequently having one database is impossible. As to the Wikispecies
being multi-lingual, at this moment in time two languages are the
languages of taxonominal science: English and Latin. So the question is
why should Wikispecies be multi-lingual, and should it be Latin or
English :) ? Obviously, Wikispecies would be a resource available from
within all wikipedia by the same syntax.
Using the taxons (species genus kingdom etc) as a category is in my view
not a great idea. The taxobox would be part of each article and
consequently the information would already be there.