I visited Japan in February for WordCamp Fukuoka and met a developer there who created a great WordPress plugin - Head Cleaner. It parses the output of the head element of your pages and cleans it up. It puts all of the tags in an order which I believe is good for SEO. Meta tags are moved to the beginning of the head element. After the meta elements it outputs the title, followed by your link tags. Then it puts in the script tags. It also removes any unneeded space between elements.
In theory a clean head should make parsing easier for search engines. Search engines don’t really care what CSS files you use or where you are pulling your Javascript from but they obviously care about your content.
Head Cleaner also allows you to combine and compress your Javascript and CSS. It also enables you to move Javascript to the bottom of the page. This method is appropriate for unobtrusive Javascript files that run after the page has loaded. You can also select Javascript files you don’t want to include on the page. Sometimes you might have an older plugin that includes an additional version of jQuery. I’ve seen some sites that are loaded with tons of Javascript files that could be helped greatly by the functionality of Head Cleaner.
Another nice feature is the ability to remove filters that run in the head. Sometimes your plugins may include a filter that you might not want to run due to incompatibilities with other plugins you are using.
There are many more features and I encourage everyone to try it out on their WordPress site. Some features work better if you have caching enabled on your WordPress installation.
The developer, who can be found @wokamoto on Twitter, is going to be speaking at WordCamp Yokohama and was also responsible for putting the site together. He has a nice series of posts on his site that detailed his development process and what plugins he used. Unfortunately it is in Japanese but the lists are in English.
