I think there is nothing wrong with link sharing as long as it follows these rules:
1. it is for a legitmate website without malware
2. the link sharing is done no more than once or twice to each recipient, unless the recipient is truly interested in the link being shared (than you can share 100 times and it would never be spam)
In other words, since everyone wants links to their websites, me included, I think it is ok to share a link at least once with each person, maybe even twice. Once you start sharing links more than twice with the same person and that person is not interested, it is spam.
Hey, for all you social media marketing experts out there, I am sharing SocialSkyline.com where you can find paid social media marketing projects.
I am sharing this once, so I do not believe it is spam.