I wonder if nowadays not being on LinkedIn will result in people not getting hired?
If you go the ol' "send in the blind paper CV" submission route it will likely go to "file 13" unless you direct it to someone with whom you have made a connection on the inside.
What's nice about LinkedIn is you can invite people to make those essential connections with you through points of professional and academic commonality. You'll learn of such points by looking at posted profiles.
You have to be the kind of person folks will want to connect with so it is essential to have a sharp and accomplished profile -- just like you would need to have on a CV. You can link your CV or your website to the profile and make learning about you effortless and not overly time consuming.
I joined in 2008 and have made connections with ~ 2200 people. Landed my first project using LinkedIn within 30 days and over the 6 months from Sept 2008 - March 2009 the project paid >$100K. Not bad at a time when the economy was in such a downturn post Wall Street collapse.
More to your point though: yes, I think LinkedIn profiles will be used more and more to identify skills sets for employment and for projects which require customized (or customizable) skills sets. It has helped me connect with a lot of old colleagues both academic and professional, and it has allowed me to connect 1 on 1 with some very highly placed decision makers (and I mean the check signers.)