I have complied a list of essential WordPress Plugins and services to get your blog up and running. I highly recommend them all as I have personally used them and have had no issues with them. This list shall be updated as I discover and test new tools.

Discussion Tools

• Contact Form 7
  Simple but flexible contact form.
  
  • view form

• Action Comments
  Action comments is a great way to quickly build your email list. It gives your commenters the option to opt-in to your list

• DISQUS Comment System
  Highly recommended comment system hosted and powered by DISQUS.

Email Marketing

• Aweber
  Send email newsletters and autoresponders with ease.
  
  • View Blog Post

• Opt-In Form
  Customize your own opt-in box for your blog.

Feedback Tools

• SurveyGizmo
  The SurveyGizmo WordPress plugin lets you access and monitor your SurveyGizmo.com surveys remotely

• WP-Polls
  Run a poll on your blog with WP-Polls
  
  • View Blog Post

Mobile Tools

• WordPress for BlackBerry
  Create, Modify and Publish your blog posts on the go
  • View Blog Post

Membership Site

• WishList Member
  Turn your WordPress blog into a membership site.

Optimize Your Blog

• WP Super Cache
  Reduce you page loading times by applying this cache plugin.

Share Your Discoveries

• TweetMeme Retweet Button
  This plugin adds a button on your page which lets readers to retweet your blog post

• Add to Any: Share/Bookmark/Email Button
  Help readers share, bookmark, and email your posts and pages using any service.

• TwitterFeed
  Automatically feed your latest blog posts to Twitter.
  
  • View Tutorial

SEO Tools

• All in One SEO Pack
  A complete SEO package for your blog (Highly Recommended).

• Google XML Sitemaps
  Once installed this plugin alerts search engines of changes to your blog by generating XML sitemaps (Highly Recommended).

Statistics Tools

• Google Analytics for WordPress
  If you are keen on your blog stats, conversion rates and more, then this plugin will do just that.

• WordPress.com Stats
  Another great stats plugin for on-the-go results. It tracks post/page views, referrers, and clicks

• TwitterStats
  TwitterStats is a great way to graph your twitter activities such Tweets by hour, Tweets by month, Tweet timeline, reply statistics and more

Social Networking Tools

• Twitter for WordPress
  This plugin allows blog readers to view your recent tweets.

• Flickr Photo Album
  Bring Flickr pictures to your blog

Task Management

• Remember The Milk
  Remember the Milk is a fantastic tool for task management and to manage your to do list

Protect Your Data

• WordPress Database Backup
  On-demand backup of your WordPress database (Highly Recommended)

Utilities

• Exclude Pages from Navigation
  Great tool to exclude private pages from you navigation.

• WP Greet Box
  A smart plugin that displays a customised welcome message to your visitors based on the site they are coming from.

• Contextual Related Posts
  Display contextually related posts within your page.

Video Tools

• Vimeo for WordPress
  Add vimeo videos by selecting the video from the drop down lists or adding the URL of the vimeo video’s page in the box