Plaxo began as online address book and then calendar exchange, a way to maintain updates by letting users maintain their own profile and chose with whom they share it. This year Plaxo began offering lifestreaming, Pulse, aggregating comments from friends and affinity groups. It also maintains detailed profiles with distinct views for personal and professional lives, and shares them only within categories of contacts.

Designed for installation on blogs, Disqus becomes the comment system. It organizes comments around not only the blog, but also the comment and commentary, almost akin to lifestreaming services such as Jaiku and FriendFeed. Unlike lifestreams with comments, Disqus doesn't fracture the commentary; it is the commentary—the one designated by the author.

Run by a Finnish company in accord with European privacy law and standards, but now bought by Google, Jaiku streams feeds for friends and others to discover and read and also channel into SMS alerts. It also imbues this capability for groups.

Whether some stories truly need condensing editing to 1000 characters, or suffer it tolerably, Clipmarks can excerpt and share only that, though it allows another 1000 for commentary and numerous additional pictures, each worth maybe a thousand words. In addition to viral appeal in way of a Facebook app, the new Clipcast interface looks and works like a widget, perhaps to target mobile users. For this category, a thousand character summary of a page would then seem ideal! Linkmarking, indexed from terse to featureful, might go Reddit, Del.icio.us, Digg, Google, Yahoo, MyWeb, Clipmarks, Ma.gnolia, Faves (Blue Dot), Tumblr, and Google Reader Shared items.