When you decide to add a twitter plugin to wordpress its a matter of  choosing one that does most of what you want and then, if possible, another one that can fill in the gaps, so rather than choosing one single twitter plugin you should consider two (sometimes, not all the time).

Choose a twitter plugin for your wordpress blog.

Just to make the life a little easier I have short listed a range of plugins (some I highly recommend) to make twitter and your wordpress blog work together.

• TweetSuite

  A widget enabled plguin for twitter that has some pretty cool features. *Recommended.

• TweetBacks for WordPress
  

  This wordpress plugin imports those tweets about your posts as comments. You can display them in between the other comments on your blog, or display them separately. *Recommended.

• WP Twitip ID

  Plugin adds an extra field to the comment form for user to enter their twitter username.*Recommended.

• Tweet This

  Add a Twitter icon to every post and page, so your readers can share your blog entries via Twitter with a simple click of a button.

• The Twitter Updater

  Automatically send a Twitter status update to via this wordpress plugin to twit your followers when you create, publish, or edit your WordPress post. I wouldn’t recommend this to be honest, as people wont find it interesting that you just changed an A for a Z or added a full stop in.

• TwitThis

  This wordpress plugin sends Twitter messages about your blog post or website via TinyURL.

• Twitter Tools

  This wordpress plugin creates an integration between your WordPress blog and your Twitter account. Pull your tweets into your blog and create new tweets on blog posts and from within WordPress.

• Twitter Badge

  Display badges showing what you are posting on Twitter via this neat wordpress plugin .

• Twitter WordPress Sidebar Widget

  Customise the number of updates shown in your sidebar, individual links to each status update on Twitter, style your Twitterings using CSS, choose whether to display your Twitter name before each post and customise text between the post text and the relative time.

• Twitt-Twoo

  A simple but useful wordpress plugin that allows you to tweet directly from your blog.

• Twitter Feed

  Posts your blog updates to your twitter account via OpenID.

Well thats about as full a list and breakdown of different twitter plugins for your blog.  Hope they come in useful, they should do!