Without further adieu, here’s my list of preferred plugins for WordPress blogs:

Akismet – There’s a reason this plugin comes standard with every WP install.  It’s the only spam plugin you need.

cforms – I have cforms installed on my site, but I don’t currently have a form up.  Basically, it’s a killer contact form plugin with anti-spam tools built in.  Here’s one in action (look on the lefthand side).

Exclude Pages from Navigation – So this plugin doesn’t have the most creative title, but it is accurate.  If you want WordPress to behave like a website CMS, then you’ll need to control your recurring navigation.  This plugin allows you to do so.

WordPress Database Backup – Backup often, backup automatically.

WP Super Cache – A fork of the original WP-Cache 2.  Stock WordPress calls its database on every page load, which is slow.  Super Cache generates static html files and serves them to your visitors, making your WP site much faster.  No matter your server, you won’t survive a front page digg story without Super Cache.

All in One SEO Pack – This plugin allows you necessary control over your title, description, and meta keywords (which are probably not necessary.)  It allows some control over the robots meta index/noindex/follow/nofollow tags.

Robots Meta – Another one from Joost.  This picks up where the SEO Pack left off.  It allows control over the robots meta of every page/post, and gives you more control over your archives.

RSS Footer – Again from Joost.  This allows you to add a footer to your RSS feed.  I use this to add links back to my real estate blog, which helps Google learn who the original author of the content is.

Quiz Master 3000 – My first attempt at designing (not coding) a plugin.  This plugin allows you to create simple quizzes for your visitors, and encourages the quiz taker to display their score on their own blog.  Here’s one in action.