Nice work! I actually created something very similar <a href="http://friendorfollow.com" rel="nofollow">http://friendorfollow.com</a>.<p>The hard part is dealing with Twitter's API rate limit and scaling. It's nearly impossible to pull down the data for large accounts like @aplusk. 5k id's at a time, pulled synchronously (due to Twitter's API paging system), by the time you're able to get all the data, he's already received 1k new followers.
It seems to max out at 5000 followers (which makes some sense because the default behavior of the twitter API is to return the first 5000 ids)<p>This may seem nit-picky, but the main cool-factor of this is to see which high-profile people follow each other, which it <i>almost</i> works for.
I don't quite understand the point of this. What's the benefit? Isn't this the exact same thing as going through my Followers list on Twitter and looking at which ones don't have the blue "Following" button next to them (which would give me the more interesting metric, people whom follow me but I don't follow)?
This is one of the many possible ways of viewing twitter followers.<p><a href="http://www.justunfollow.com" rel="nofollow">http://www.justunfollow.com</a> provides many other views:<p>1) Tweeps you're following but not following you back.
2) Tweeps following you but you're not following back.
3) Tweeps who recently unfollowed you.
4) Tweeps who recently followed you.
5) Tweeps you're following but haven't tweeted for the past 1 month.
6) All the tweeps you're following.