Spam takes many forms on Google+. There is the age-old churn-and-burn method, which is essentially based on posting the same messages and dropping the same links to multiple communities with many members. These spam messages are easy to spot, because they scream spam, and they are the bane of many Google+ community owners and managers. The basic plan is quite simple: slip through Google+ spam detection system, and gain as much exposure as possible, in the hope that there will be traffic that could be converted, before the spam posts are removed by the owners and moderators. I have always questioned the efficacy of this method, since I cannot see how it can generate sufficient number of leads, though it must be working, since spammers are not spamming for fun but as a business.
There are more elaborate, more insidious, but cleverer schemes. I consider them as spam, but others may perhaps not. This method can be termed as creating a network or web of spam profiles, pages, and communities, that obtains legitimacy by gaining genuine followers. The individual posts in and of themselves would not in many cases meet the threshold of spam: they survive the duck test, since they do not look or sound like spam. The ultimate aim must be to generate revenue in one way or another by promoting a website, and make money by means such as advertisements, selling some sort of product or promoting an MLM scheme, or exchanging influence for money. The modus operandi of these spammers is to create a network of profiles, pages, and communities with sufficient followers, members, and engagement, employing tactics such as circle sharing, which seems legitimate, therefore obtains sufficient immunity from automatic spam detection and from user reports.
Given the high impact of the visual and the audio-visual on Google+ (and indeed other social media platforms), these networks will create a number of profiles, pages, and communities, and share striking photographs, funny memes, and popular video clips, with varying degrees of dubiety in terms of respect towards others’ copyright and intellectual property. As alluded earlier, the method is subtler and the Google+ entities in such spam networks will only drop links occasionally, scattered among ‘interesting’ materials. The key is that it is not a single Google+ page or profile, but there are many, which will then follow each other, giving an illusion of popularity, which in turn will result in genuine followers, who think that the spam profiles, pages, and communities are the real deal. Because there profiles and pages are enmeshed, other profiles and pages in the network will be surfaced as suggestions to be followed, posts by other entities in the network will be reshared and +1d, thus amplifying the potential reach.
This method is nothing new and it is not unique to Google+. It happens with websites with the intention to manipulate search results, and it happens on other social media platforms. Playing the long game, the individual(s) behind the network may be working on the assumption that interactions within the Google+ landscape will be beneficial for their posts (some with dropped links) in searches conducted or recommendations highlighted on Google+ and even in Google personalized search results. Naturally, once gaining a good gauge for the numbers, it would be possible for the network to promote goods and services in return for money, especially as the views count on profiles and pages, individual views count on images, and Insights data for Google+ pages give pertinent information about reach and demographics.
The insidiousness of such networks lies in the strong possibility that many genuine users will become unwitting instruments for spreading spam or advertisements in disguise. It would be interesting to see if such spam networks will be successful, and how Google will deal with the situation: the important thing as a Google+ user is to be selective about whom to follow. I only follow Google+ profiles and pages that I find interesting and look genuine, even then I might be following one or two profiles and pages that are part of a network that I have described.