Is Blogger viable?
Anyone try to make their own?
but how do you know what the right questions are?
does this mean that one would need to "market" their notebook to the right crowd? or can this happen naturally?
follow basic rules of blogging and web marketing, target your discussions - having a constant theme will help build an audience that returns consistently, provide useful information, if people find that what you have to say is important they will come back
software that allows people to keep some information private, but allows them to make it public when they are comfortable
impact with web analytics
tracking conversations on twitter and social networks
Designed For Science but not necessarily social networks, Research Gate, Academia, Mendeley
Repository for open notebooks
automated content addition
live conversations (standard now on most sites)
geotagging integration, basically foursquare or something like that that would allow people to arrange meet ups for beer or whatever.
publication sharing, in case this is something beyond sharing links (uploading and sharing pdfs or .docs)
integration with cloud software, google docs, flickr/picasa, twitter, other social sites