if you don’t partake in common link schemes with common, obvious footprints:

Paid links
Your own websites
Link exchange programmes
Low quality guest posts
Distributed articles
Low quality directories
Fake user profiles
Social network or bookmark spam

…. then you’re probably OK

according to SearchMetrics ♦ 5 of the Top 6 ranking factors are “social”

social signals + social shares are becoming way more influential in ranking a web page

those who create + curate + syndicate killer content that gets liked + shared + plus 1′d and is connected to your G+ rel=author credentials

the more social signals coming from your Author Rank creds ♦ the more your AR will improve and impress Google

I like how Rachel defined the currency of the new economy in her awesome TED Talk

http://www.ted.com/talks/rachel_botsman_the_currency_of_the_new_economy_is_trust.html

The currency of the new economy is trust

I think a little more clarity may help.
In the list of common/obvious items – not all distributed articles are ignored.

Press Releases are a fine example of some that may count.
As per usual – it seems to be dependant on Quality and Volume.
(I honestly doubt G will consider all 200 links from 200 reprodcutions – but I don’t think they discount all 200 either … the evidence suggests that at least some of the more prominent sites get used)

Link Exchanges is another questionable one.
How to tell the differenfce between an exhange and reciprocation based on respect/appreciation?
Aside from volume, location/destination and timing … all of which can be fiddled with … the only other indicator I can think of is seeing a simialr pattern repeat itself.
So the key there is to only dfo it a little, infrequently, with a random delay and monitor the pages/link text etc.

And then we have mutual sites.
I call Google out on this one – as I’ve seen sites benefit from links from their own sites … and I happen to know that G may well have a threshold of sorts for certain patterns/limits.