Link away! And be sure to join a bunch of groups related to what you do or your skill set. That's how recruiters find you. Recruiters reach out to me regularly - and do the same to my co-workers. I know people who've gotten jobs that way.

Interesting; in my circle, linkedin is widely considered to be "unserious". An individual's so-called endorsements are heavily biased by friends and people outside the profession so as to be completely unreliable. Bona fides are established through direct interaction and networking occurs face-to-face. If we were looking to hire someone, we wouldn't bother looking at linkedin -- we'd get direct references from the individual and have in-person meetings.