"Search engine optimization does not specialize in tasks that will make pigs soar high up in the sky. Its real task is to dig deeper into the genetics of a website and reengineer the essential elements until it transforms into an eagle."
"...The objective is not to "make your links appear natural"; the objective is that your links are natural."
Matt Cutts - mattcutts.com
"There's been so much fear pushed around the web about reciprocal link exchanges and link trading programs that the message has been muddled up into the completely nonsensical "never link to someone who links to you." To my mind, that's a touch of lunacy."
Rand Fishkin - seomoz.com
"...the time has come to ask yourselves does your blog suck ... and what are you doing to change it?"
"The success of a page should be measured by one criteria: Does the visitor do what you want them to do?"
Aaron Wall - SEObook.com