I should have guessed it, as popular as twitter is among bloggers (for good reason), several wordpress twitter plugin have been built.
The first one I tried was Tweetbacks. The first time I used it I had a few thousand twitter spam/error comments added to my comment section. That was not going to work for me. I saw others where having the same problem and was about to uninstall the plugin, but two cool things happened. I could use TweetBacks clean up tool to get all the tweeter comments out of my database. And the plugin was upgraded. When I activated it with the newer version, my problems were gone.
Tweet this blog post and see if your twitter comment doesn’t show up here, maybe not immediately.
Retagrr is not a wordpress plugin, but a widget that will add your social media contact information and tweets to your blog. You can see this at the top of my right sidebar.
Tweet This plug in makes it easy for your readers to tweet your post on twitter. You have various options, under settings you can click Automatically insert tweet this links and you’ll see a bird like this at the top of your posts. Choose which of 6 url shortening service you’d like to use.
Or if you prefer, also check the box for Automatically insert a small link at the end of posts instead of a large icon at the top-right and it will look like this:
WP Twitip ID
WP Twitip ID adds a twitter id field to the comment form and when your readers comment, if they add their twitter ID a Follow Me link is added to their twitter account. This plugin was harder to use as it requires editing the theme’s comment.php file. Be sure and watch the video on the page for help in this.
PingPress fm is another plug in I’ll check out, thanks to @bluefur It sends out your blog posts to ping.fm . Which in turn updates many social networks.
I found other twitter plugins for wordpress I’ve not checked out yet:
10 Best Twitter Tools for WordPress Blogs
Top 5 Twitter Plugins to Incorporate into your Blog
This link will lead you to more WordPress Twitter Plugins
Update: Video on adding Tweet This plugin to your wordpress site