Meshly is a new nanoblogging platform that's built around publishing via instant messages. Users can create and publish posts in AIM, Google Talk, or Windows Live Messenger using IM bots. Creating posts is like having a conversation with someone. Type "post" to the IM robot and it will ask you to fill out the post title, body, links, and tags, before it publishes the content to Meshly's post queue.
Once post are there, other Meshly users can vote to decide which ones are interesting. Stories that have piqued enough user interest will be promoted to the front page, which is a system closely matching Digg's.
I'm not sold on the usefulness of a system that enables posting only via instant messenger (instead of a browser and/or a mobile platform). Nor am I sold on the system's ability to scale to something the size Twitter has become. Just a casual glance at the front page of Twitter shows that all of the public posts have happened within the last minute--hardly something that can be kept track of easily. Digg has gotten around the problem of dealing with the huge amount of submissions by adding a cloud feature that groups together tons of headlines.
Adding a rating system on tiny blog posts to corral them is an interesting idea. I'd like to see something similar done to Twitter's limited favorites system, which becomes cluttered quickly for heavy Twitter users. For publishing, though, one of the things that makes services like Digg, Twitter, and Tumblr so great is their easy-to-use publishing tools.