I found this session really interesting to introduce me to a bunch of Twitter tracking tools. I've experimented with a few before. I'm just going to mention all the ones I know about in this post.
One I've used for a while now is "Twitter Counter". The free version of this tracks the number of tweets you make and the number of followers you have. You have to upgrade (pay) to export this, or see mentions/retweets, or to track back longer than 6 months. One thing I like is the ability to plot trends over long periods, and plot both number of tweets and number of followers on the same graph. I see interesting patterns in that. For example this screen shot from Jan-April 2012 shows the rise in followers I got from tweeting at the UK National Astronomy meeting in early April 2012, and also a boost from tweeting a lot during Stargazing LIVE (Jan 2012). My theory that your number of followers is proportional to the amount of time you've been tweeting is also based on these graphs, which seem to me to have rather constant gradient over long periods... at least for my account.
My conclusion from this is that number of followers isn't everything when it comes to your Twitter impact - but that's probably fairly obvious. However I do think tracking these trends is a good idea.
Another one I stumbled on that I kind of like is Favstar.fm which tries to work out what are your best performing tweets. I find that sort of interesting - seems to be based just on number of retweets and "favourites". Some interesting results for me.
My best tweet so far surprised me:
I've also tried out Klout, mentions of which (from others) received at best mixed reaction in the room during this session. True - it's a bit over simplistic, but it's probably also the most recognisable of the results (beyond number of followers) - it's tagline has turned into "The standard for influence". However, I opted out of Klout a little while ago after reading this article sent to me by @eddedmondson: "Evil Social Networks". If you sign up, you also sign up all of your followers (without their permission). Lots of people disagree with their results too. To opt out of Klout you can visit this link. Peerindex was mentioned as similar to Klout, and doesn't have the same opposition (at least that I can find online), so may be a better option if you want a single number. I'm signing up for this as a write.
Probably the big winner of a recommendation from this session was CrowdBooster. I joined this service yesterday following the session and I've been impressed so far. It seems to do both the tracking of raw numbers, and the analysis of the most popular of your tweets in one location. I like the first plot showing the reach of tweets (basically the total number of followers of everyone who might have read your tweet based on who retweeted it). The statistics on influential followers and who retweets you the most also look useful.