Your blog promotion is a project. As every project, a constant feedback is required to determine of what is working, and what is not. While many free opportunities are available for bloggers to check statistics, post popularity, and keywords success, sometimes you need to check the effectiveness of a single link and get instant notification, when somebody clicks it. Well-known approach would be to make a short URL at one of the redirection services, where detailed statistics are available. However, this approach, while being quite effective is also passive, since you need to check the stats manually to see the results.
LinkBlip (http://linkblip.com/) offers you even more proactive approach. This free service will send you an instant email notification as soon as link you provided is clicked by someone. This email notification includes the time your readers clicked on the link and their virtual location (the city and state they are in). There service is absolutely free, and does not require registration (definitely, you need to provide your email address, where notification is supposed to be sent).
Note that this simple, but quite effective service for some specific tracking purposes, is currently on sale. Visit it at http://linkblip.com/ and buy, if you are interested.