How is this service different? - Most of the Add to Twitter services asks the user to login to some third party site to post the update to twitter.
My twitter button will automatically shorten your url using http://bit.ly and will redirect you to twitter to post the new update
So you needn't login to some other sites to post your blog post update to twitter..
Here are the steps to add the Twitter Button
If you are already using my social bookmarking icons
1.Go to Blogger Layout > Edit HTML
2.Delete the code that looks like
<!-- Social Bookmarking Icons End www.bloggerplugins.org-->
3.Now add the content from this text file over there.
4.Save your template and you will get the social bookmarking icons including twitter
If you are new to my social bookmarking icons
1. Follow all the steps @ Inserting Social Bookmarking Icons for Blogger and you will get a full set of social bookmarking icons on your blog.