SEO sniper was pretty cool but has been recently discontinued. All in One SEO is a good all rounder, but headspace 2 is the most advanced suite.
I was intending to ask the same question. Sorry if it sounds stupid, but I'm curious as to what SEO plug-ins actually do. Any information would be appreciated
I like headspace2. People usually list all in one because it's easier to use. Headspace2 is a little more complicated but it's also more in depth.
The best wp plugin you CAN'T buy is one we are still beta testing The 'unique content generator' plugin. Any topic and quantity. Sorry to tease, but you did ask, and we are using it ourselves...
The best for me is Platinum SEO. In fact it is All in One Seo Pack with some enhacement that let you play with follow/nofollow, index/noindex links. This way you can avoid contect duplication when Google follow tags and categories for example.
Don't forget to make all your urls "seo friendly". You can easily do this by changing your permalink structure. http://www.gnc-web-creations.com/wordpress-urls.htm
The best seo wordpress plug in IS Headspace 2 however the easiest to use is probably all in one seo plugin. http://back-links.org/21-wordpress-plugins-you-must-use/