Nofollow backlinks – are they useful?
Obviously there are two crowds when talking about nofollow backlinks. Some people are strictly backing their opinion with search engines guidelines, that clearly states that they do not follow these links, therefore they don't use them as a ranking factor.
There is also other crowd, not sure how big compared to the first one, thinking that the nofollow backlinks are being used by SE for ranking purposes even though people from those companies openly deny it.
Where the truth lies? Is there any reputable case study about nofollow backlinks? Is it even possible to find out?