the intent behind many of these sites is that they are tagged with keywords for specific audiences. one could create a site more generally geared towards neuroimaging, but this one is meant to cover any topic related to neuroinformatics. it's a very broad domain, but some areas it would cover, in relation to neuroscience, are:- ontologies and lexicons- computing and database infrastructures- usage questions of tools and resources- questions that wikipedia does not have the answer tothe use of such sites as a discussion forum have been argued a fair bit. but a typical rule of thumb for questions on such sites is that only questions that can be answered objectively are allowed.