Many courses on battling sexual temptation and pornography (like www.settingcaptivesfree.com) refer to having someone as a accountability partner. The accountability partner is the person who checks on your progress with the course and also makes sure you are keeping away from any kind of temptation sources like TV, video and Internet.
Now Twitter is an online tool where you can tell the whole world (or a group of friends) what you are doing. And this is interesting. If you are able to update your Twitter at every event that takes place in your daily life, this can turn into your accountability tool. If you have a friend, you can share your twitter only with him or her and that way the whole world need not know either.
But of course, sincerity and being committed would be key here.