This video by Jessica Swanson of Shoestring Marketing, lists her 10 favorite open source plugins. There are some really good plugins among her choices. The one I might question would be WP Super Cache. Plugins like this do work. They make for happy search engines as advertised.

But they also get plenty of love from hackers. Hackers use the static pages rendered by the cache plugins to study your site so they can discover openings to exploit. While it is O.K. to cache many pages, any that contain downloads or other info you do not want everyone to see should be excluded.

There is also a risk of the parent site serving the cache being hacked. This has already happened once, to two of the top cache plugins. To their credit, the two companies involved acted with haste and quickly regained control of their user data. That does not remove the danger however.

Ultimately, the decision on rather you are more concerned about security or Google love is yours. All I can say is if you choose to use cache type plugins be careful what plugin you use and be smart about what pages to exclude.

All In One SEO is a solid SEO plugin that really does take care of most of your SEO needs with WordPress. SEO Friendly Images adds an important alt tag along with a description for all images.

Google XML Sitemaps is yet another SEO plugin. This is a great addition and takes all the work out of keeping an updated search engine friendly site map. Another useful choice is the Broken Link Checker plugin which does an excellent job of finding broken links in your site and notifying you about them.

http://www.youtube.com/watch?v=4eBU0xwnKG4&feature=youtube_gdata

Download The Plugins From The WordPress Plugin Directory By Using The Links Below:

All In One SEO Pack

SEO Friendly Images

Google XML Sitemaps

Broken Link Checker