I've never gained anything beyond mountains of spam from IT recruiters from LinkedIn.
Does anyone (here or anywhere) gain anything from LinkedIn?
If I have meetings, e.g. with VCs, LinkedIn is useful to get a bit of background information on them.
It has got me in touch with a couple of college friends I had lost touch with, a former co-worker likewise, maybe a cousin.
Business value? No.
I got a job offer from Google that started from them finding my LinkedIn profile. That said, I despise them more than any other major website. Their entire business model is holding the information for ransom that you provide them to make available to the business world. I'd love to see a YC company replace them, or do so myself.
Rapportive is pretty cool tool to have. Aside from the standard NSA paranoia stuff mentioned in the article, what's the real danger for an average person who wants the rapportive experience on mobile?