Blogware is a general term encompassing software to create, edit, manage and publish weblogs (blogs).
Blogware may be commercial off-the-shelf "boxed" software, shareware, server-installed open source scripts or a hosted service. Examples include Movable Type by Six Apart, b2evolution, WordPress, TypePad , Blogger, LiveJournal, JourURL and blogware
Owen at asymptomatic.net has a very good chart comparing server-side blogware.
While all blogware is different, they seem to offer some common features such as facilitating authoring and editing of blog posts or articles, various linking and syndication features, and the ability to easily publish the blog on the world wide web.
Some services or organizations are also creating blogware with extended features to aid communication such as surveys in The TeleInterActive Press or wiki capability in Socialtext