Once you move into that level of Twitter, you will begin to think about how to advertise and grow your Twitter account. While you can always post an RSS feed of your account or install a widget, people don't necessarily take the time to read your recent posts. In fact, most posts aren't really attractive or well thought-out, so they won't draw in many of your site's visitors.
TwitterCounter. Similar to other counters such as hit counters and FeedBurner's Feedcounter, TwitterCounter is a chicklet for tracking the number of followers you have on Twitter. Here is what it looks like with my other chicklets on my sidebar:
Once a user clicks on the TwitterCounter chickelet, it takes them to a page that gives the stats about your Twitter feed's growth. Most prominently is a chart detailing the last week's "following" numbers for each day. My chart here is pretty boring, but it does show the day that Twitter accidentally "unfollowed" a bunch of accounts in an attempt to fight spam.
Another nice feature is the overall statistics that TwitterCounter keeps. It's a good way to look at your long-term growth, average rate of growth, and even a prediction for the future of your feed. I'm not sure how it gathers the last one, but I'll be pretty happy if I pick up another 11 users in a month.
While at the moment TwitterCounter doesn't have a lot of features besides what I've pointed out, it's still a nice chicklet for your site and you can even customize it. Give it a try if you've noticed your feed has started to grow. If you already use it, let me know what you think!