What role does social media play in an SEO strategy?

[goyalenergy]

What role does social media play in an SEO strategy?

[Fli]

In this video (https://www.youtube.com/watch?v=udqtSM-6QbQ), Matt Cutts from Google talks about this topic. From what he says i dont see Google takes social mentions in account much, but it might be wrong / outdated info.
At least some social ontopic mentions can be beneficial to raise website traffic "little bit" i think

[SoftDev]

Mostly people focus on social media just for highly targeted audience, TBH I don't care about SEO, if my social media traffic is converting well rather than SE organic one.

[supercutting Tools]

Social Media are the good way increasing the Traffic ranking of website. SEO is the Long Term Process increasing the Keyword ranking of website.

[happynew]

Social media is not only important for extra views to your blog it also help in your ranking.Getting views from Google + may fetch you astonishing results in SERP.

[MarvinWarren]

SEO is dependent on social media because it provides advertisement worldwide and views. All the social media sites have high PR so it helps increasing the PR of the site under SEO.