Tweet Progress is a directory of progressives on Twitter. A couple weeks ago, Twitter rolled out a new "lists" feature that lets people curate their own list of Twitter accounts, then others can follow those lists to see just the tweets from those people. This is great, and obviously I should make lists for all the people in Tweet Progress.
Only it was a little more complicated than that. Twitter limits each list to a maximum of 500 people, and each account to only 20 lists. There are over 4,000 Tweet Progress members so there was no way to create one big list. So I had to figure out some way to split up the list, but not too much or I'd run into the 20 list limit, and I didn't want to just do the top 500 with the most followers, since that doesn't really fit in with the spirit of the project. And I definitely didn't want to make any kind of editorial decision as to who should be included or not. There had to be a computer algorithm sort of way to do this.
Mentors and Newcomers is similar to what you see on the Tweet Progress site, limited to the most recent 100 newcomers, and the 100 most influential mentors. Influential and Highly influential is based on Topsy, a great search engine for links shared on Twitter. Similar to how Google uses a 1-10 PageRank to rank web pages, Topsy uses a 1-10 metric to rank users, based on how frequently they are retweeted, who retweets them, etc. (more details here) They display this on the site with an "influential" and "highly influential" tag. I've incorporated that information into the Tweet Progress database and that's how those lists are determined.
I've just started playing with the results, and I can say that the influential and highly influential lists are exceptionally useful, you should definitely follow them to stay on top of what matters to progressives.
If you want to be included, just join Tweet Progress. The lists are updated automatically every night.
Also, sort of related, you can use GovLuv to create a Twitter list of who represents you in government -- federal, state, local.