Being on LinkedIn has never really done anything for me as far as I can tell. Perhaps I don't use it right or something. Maybe it's something that takes active participation. No one has ever contacted me about an opportunity and said "I saw your information on LinkedIn." I get requests from Dice and CareerBuilder all the time. And someone endorsing me for a skill that they don't have really means nothing to me. You're an accountant and you're endorsing me for Network Security? Um, what do you know about that. It would be like me endorsing someone for their excellent mortgage lending skills. Pretty useless.