Content that we want to share ...

Even Google, through its PR Matt Cutts, wants the webmaster to make pages the user want to link, and it is explained in this article: Linkbait and linkbaiting. Here his definition:

"Anything interesting enough to catch people's attention".

There are pages that command attention and cause the reflex to share them on social sites. This has the advantage of providing natural links, a more correct method than others, such as registration in a lot of directories with no visitors.

The content users are expecting ...

Provide useful or necessary information. Information that can be given because the author has experience in the field, or because he has a connection with a member of the staffs who informs he. So this form of linkbaiting require you demonstrates firstly that you are a reference in this field.
A new that you are the first to provide. Or alternatively, the fact that you provide more information than other posts on the subject. This requires learning about topical issues and be ready to provide any relevant information as soon as news come.
A script, program, a unique Web service , and that the intended audience may find useful.
For such a product causes links, it must meet for approval. We must express what others think in a way they could not have imagined themselves. The ability to add comments promotes awareness of such articles, even in the case that follows ...
Or on the contrary, writing a post that goes totally against conventions and which raises many reactions, makes other post refer to this article. Creating controversy is fairly common to be publicized as we know.
Top 10 or statistics
Provide top 10 products or sites, or provide unique statistics. In the second case, the site should have an heavy traffic.
Providing a complete list of websites in a field, a list of software. In some cases you get links from the sites listed also.
A photo, a video or a story about something unusual. Anything that is astonishing.
Unhold proven ideas
And apply them to new situations. Another recipe from Grandma, but still a way to do more with less.

And qualities of this content...

For example...

The reader is impressed by what he sees. This may be an accumulation of facts and images that reinforce the impression, or simply the quality of the presentation. A photo can produce an effect of wonder for the beauty, the grandeur of the scene. The same effect can be produced by a text.
Why would you link to a page if you doubt the quality of the author to talk about the subject? Gaining recognition as an expert in his field is obviously not easy and can take time. But if it succeeds, is the assurance of seeing backinks flow.
Number one
Create a site that is the most important resource on the Web. For example, the largest number of tutorials on GIMP. The number 1 always attracts votes, as in sport.
A touch of humour is always welcome. Without necessarily turn its site into humorous place, if you find a funny approach to something that is painful, it is a quality.
A new angle
This is the resource of the poor man, but whose supply is never dry. Talk about what everyone is talking make it difficult to emerge from the anonymity but if we show the facts in a new, unexpected, surprising viewpoint.
And the look and feel
A crude design with flashy colors, the use of tables for layout,intrusive graphics effects, will void all the benefits that the content might merit: nobody will link to the article.
The menu of the mobile section of this website gives you an example of original look, with some CSS properties.

Participate to a Web where the links do not come from exchanges or similar processes, but are brought by a content one wants to share with others ...