I’m not deeply involved in the SEO business but it’s generally a good idea to get those META tags straight. If you are only remotely as lazy as I am you will probably welcome Richard ‘Rich’ Boakes wordpress plugin ‘autometa‘:
This plugin will automatically generate and include HTML Meta Tags and Technorati Tags based on the full text of your post.
It’s as easy as it sounds. One hint: If you add this plugin to your wordpress site, it seems you need to edit the already existing posts (Edit –> Save) before you get tags for them.