Despite the fact that Google's Matt Cutts says social really comes no where near links in terms of a ranking factor and probably won't anytime soon, SEOs are prepping for the ramp up of social factors in search to prepare for the future.
Now, with that, comes spam. Currently, you and I see a lot of spam in social - on Facebook, Twitter and Google+. It is everywhere. But the question is, does or will Google and Bing and other search engines be able to filter and discount out the spam.
Yea, they do, they can - it isn't too hard. It is hard, not impossible, to build social profiles with authority that are pure spam. A WebmasterWorld thread talks about "social authority" as a way to define this.
The concept isn't new, authority in social and even with other factors is a major way of determining of something is real, how real, or outright fake.
As Tedster said in the thread:
I'm betting all my work on something like this being in play for social media - and I think it will be getting tuned up as time goes on. After all, the big social sites already have some safeguards against dummy accounts, or phony "likes" and so on. Google is highly aware that people try to game social media sites, even their own Google+.
We have time - build up your social profiles. Build a social authority the right way and if and when Google and other search engines step that up as a ranking factor - you will benefit.
Forum discussion at WebmasterWorld.