Ten years ago, the Governing Board of the Academy of Motion Picture Arts & Sciences met to discuss the addition of a new category for the Oscars: Best Casting. The proposition failed, presumably because of practical concerns (i.e. Who would accept the trophy? Is the award just another Best Picture?). Still, the questions raised by the apparent need for a Best Casting award remain largely unaddressed: How crucial is the art of casting in major motion pictures? Is it fair to give actors all the credit for their “outstanding performances,” when really their so-called “achievement” is nine-tenths the result of clever — or fortuitous — billing?

After perusing the Oscar nominees that were announced yesterday, it’s clear that 2008 was a particularly good year for casting. Not to suggest that last year’s films featured better actors than in previous years, but there seems to be a trend toward utilizing actors — especially highly famous ones, of whom we “know” so much because of their omnipresence in Us Weekly and on Perez Hilton — as if they were special effects. Like sound design and makeup, any special effect serves two principal functions: to enhance the sensational experience of the film, and to render it more “real” or natural. A number of this year’s top Oscar contenders have molded their actors into special effects through the manipulation of what I will call, for short, the Tabloid Factor — that is, the network of associations related to any actor’s publicized biography.

As a relatively simple example of the Tabloid Factor at work, take Darren Aronofsky’s “The Wrestler.” Many critics have noted how “The Wrestler” seems to tell two stories at once: One is the fictional account of Randy “The Ram” Robinson, a post-career heavyweight who’s down on his luck and aiming for a comeback; the second is about Mickey Rourke, the actor who plays Robinson, and how his struggle for an extra-vocational identity is essentially the same as that of the character he plays. Watching “The Wrestler” does not have the effect of seeing Rourke inhabit the role, but — astonishingly — of bearing witness to something real. Because of what we know about Rourke’s biography, the Tabloid Factor enhances our experience of the film.

Of course, “The Wrestler” is not the first film to treat its celebrated lead as a special effect. A commonplace in entertainment journalism is to draw connections between actors’ personal lives and their roles — and it’s not surprising to see studios, and even actors themselves, fanning those flames to promote interest and thereby increase box office totals. For whatever reason, however, some of the best films of 2008 have utilized the Tabloid Factor not merely as a buzz-attracting gimmick but as a means of creative enrichment.

As gossip rags and blogs proliferate, the Tabloid Factor evolves. In her review of David Fincher’s “The Curious Case of Benjamin Button,” Lisa Schwarzbaum noted how “at any moment in [the film], two marvels predominate, one technical and the other … Bradical.” Schwarzbaum went on to characterize Pitt not so much as an actor, but as one of the film’s best-utilized special effects: “Pitt, a comely actor, is no longer the golden surprise he was 18 years ago … What he is, though, is a phenomenon of heightened celebrity. And that rarified status, combined with good grooming and exquisite digital effects care, produces the exact force field of fame needed to take our breath away in that first moment on screen when … Benjamin is bathed in light that honors the movie-star beauty Pitt is.”

The subject of Schwarzbaum’s evaluation is a sophisticated use of the Tabloid Factor. She implies that few actors besides Pitt would have been right for the part of Button — not because of Pitt’s talent, but because of his “rarified status” as both beautiful and famous. The film, drenched in themes of mortality and transient youth, does not seek to mask (as other films have) Pitt’s “heightened celebrity,” but rather employs it to generate emotional effects — to “take our breath away,” as Schwarzbaum puts it. In other words, “Button” turns Pitt’s Tabloid Factor — specifically, his perennial distinction as “The Sexiest Man Alive” — into a kind of special effect that not only dazzles the audience but also, we might say, makes the film more real. We lose the comfort of fiction when we understand “Button” to be the story of Pitt himself, of how even his superhuman beauty is powerless against time and death.

The effects of the Tabloid Factor are not always intentional; often they are not even anticipated, as when personal tragedy creates effects that had nothing to do with the film’s initial plan. Heath Ledger’s untimely death just months before the release of “The Dark Knight” is not what made that film good, but it did make it scarier and, however awkwardly we admit it, more interesting. Ledger “takes our breath away” in a manner completely different than Pitt in “Benjamin Button,” but the cause — public knowledge available outside the film — is similar.

Ledger’s example raises concerns about how filmmakers and viewers alike engage the context surrounding a film’s release. A film that relies too heavily on the Tabloid Factor to achieve its effects runs the risk of alienating audiences who do not know, or who have forgotten, what we assume to be common knowledge or prevailing opinion. It may seem incredible, but someone walked into “The Dark Knight” without knowing anything about Ledger’s life or death, and there were more than a few “Button” viewers for whom Pitt is emphatically not the paragon of male beauty. These cave-dwellers watched completely different films than we did, just as future generations will remember little about Mickey Rourke except that he was an actor with a bumpy career — unless, that is, the Us Weekly archives become required reading for every moviegoer… ever.