[WillyF]

What about the parent comment indicates that he doesn't know what he's talking about?

Here are some Matt Cutts quotes from two weeks ago:

"Over time, Google will care more about identity and social reputation."

"Links still have many, many good years ahead of them."

"We like standards that are available on the open web. If we’re not able to crawl something – like Facebook or like the time we temporarily ran into problems with Twitter – we don’t want to depend on that data."

It's pretty obvious that Google is taking a very slow approach to mixing in social signals. They want Google+ to be THE social signal, and that isn't close to happening yet. Social can be a great way to build links, but calling I definitely would not call it a direct factor at this point.

[pknight]

Links are important, naturally. When they are coming organically as a direct result of social engagement, even better. You're more likely to get social engagement if you don't compromise the human readable title and content for the sake of SEO.

But quotes like these >> rankings are largely influenced by the number of sites linking to a post are very inaccurate and wouldn't come from someone who is keeping up to date with SEO. You can have tens of thousands of links and it could actually be hurting your SEO, which is why some sites are scrambling to take down links just to recover.

It's also worth noting that you can go crazy with on-page factors, having the perfect post slug, the right keyword density, keyword rich anchor text, descriptive meta descriptions, no-follow links, a limited amount of links on the page etc and it can end up biting you in the butt: overoptimizing can hurt your google rankings. The message coming from Google is pretty clear: create high quality content and make it accessible, don't get too clever with SEO. They will only get better at incorporating social signals into their rankings.