Landing Page Tips

It’s said landing page is the most important, especially when it concerns ppc. But must the landing page always be a lead capture page, meaning just a little info. to tempt the visitor to give his email? Or, can there be more info.? Which is better?
It seems to me that the landing page should contain just a few lines to get the visitor to register for more info., most people who come via search engine won’t be patient enough to read too much stuff, anyway. This is what I feel.
Experts, please give some advice on this.

Original post by confounded