Twitter is growing as a fantastic resource of relevant traffic to sites and blogs. I encourage all my clients to utilize RSS to Twitter automation through tools like Hootsuite or Twitterfeed. I'd also encourage you to integrate the ability for visitors to Tweet directly from your blog.
I've tested a few services, including a few WordPress plugins… and eventually decided to integrate Twitter's Retweet Button. I like the interaction that the integration supplies. While other integrations require you to click, then submit from Twitter, this button allows you to login once and you just need to click the Retweet button and you're done. Anything easier will result in greater usage when it comes to the web!
Some of the plugin don't allow you to properly locate the button. I want mine directly in line with the person reading the post title. If my post title is more than one line… the button winds up dropping down since I can only position it with my post content. As a result, I integrated it manually by putting the following code above my Post Title on my main index page, archive and category pages and the single post page within my theme: