I've been following Jeff Snyder's Security Recruiter Blog for years now. Jeff is a professional recruiter in the security world, both general corporate security and IT security. He also has a professional security résumé writing service and a job coaching service for security professionals.
We've been talking multiple times about the proper length of a résumé and he recently published an article about it. At the same time, the HBR Network blog also suggested that the CV might be obsolete in a LinkedIn world.
Well, I do think you need both a CV and a LinkedIn profile. I even think you should have two CVs and a LinkedIn profile. I found that arsenal quite useful during my last series of job interviews.
The LinkedIn profile is here to attract unsolicited recruiters. It should be full of keywords and a short description of each job you had. It is public and should not contain anything not to be displayed on the
public place. If you display too much about your previous employers,
your potential future employers might dislike it.
As it will also be consulted by solicited recruiters, it should, if possible, include credibility items, such as recommendations or links to publications that will support your application.
The Short CV is here to survive traversal of HR services or external non-specialized recruiters. That's the one that should be fashionable enough, give details about your education, training, availability, etc. The professional experience part can be short enough, it should only detail your last job, in terms of responsibilities. This CV must be short, like one or two pages.
As I recently told Jeff, I can confirm this shortness is indispensable if you're applying in Latin European countries (France, Italy, Spain, Portugal, Romania and, to some extent, Belgium and Switzerland). For cultural reasons, the résumé can be a little longer in Germanic countries such as Germany, Denmark, the Netherlands or Luxemburg. Yet not too long.
The Long CV is here to help convince your potential future boss. Bring it during the (first) job interview. An interview is often a short period of time of which little remains but a global feeling. During the interview, you can give that Long CV as a new token, full of details, that will help your potential future boss remember you.
This CV should detail your past accomplishments in every relevant past job, with figures if possible. It can go in the less public areas of what you did to address real-life problems at your previous employers. It's the place to convince your potential future boss you'd be a profitable asset. As your potential future boss will invest time in its reading, he/she will be more keen on putting your CV on top of the pile because of the investment already made on it.
I'm not looking for a job anymore right now but I'd advise any job searcher to try that strategy.