Some very astute people think link popularity is purely an external numbers game: get all the links you can. The more astute know that "trust" is where it's at. It's all about trust. But finding consensus on a definition of "algorithmic trust" is a complicated thing. The way one site earns trust will be different than how another site must earn trust. And a site that has already earned some degree of trust often sees the residue of that trust benefit new pages on their existing site.
Example? I rank first for the term link bait strategies, but that page is almost brand new. Without having one single link from other sites pointing to that page, that page ranks first for a very competitive term (1,010,000 matches). Why?