NOTE: No, the headline is not spoiling a surprise... which in and of itself is surprising, since this sounds like something that could've made for a killer reveal.
For me, what continues to be the most interesting part of the Marvel Films experiment is that they keep making decisions that feel like conscious, deliberate challenges to every "that won't work in a movie" part of their material. Prior to this, every superhero movie was approached from a perspective of "what has to be done to this comic for it to work as a movie?"... but they've been doing the exact opposite: More and more, the "grand scheme" of the whole enterprise seems to be transforming "the movies" into comics so that their Universe can be carried over as unmolested as possible...
Already we've seen once thought "unfilmmable" aspects of superhero comics like genre-mixing and shared-universe continuity brought successfully to the screen, and the results have made Marvel so confident that they feel comfortable going even deeper into comic-spawned weirdness... like, say, greenlighting a space-opera co-starring a Tree Man and a Space Raccoon as "Phase II's" new Big Shiny Thing. And now, we may possibly be looking forward to comics' infamously loose rules of mortality coming over as well: Yesterday at NYCC, Joss Whedon, Kevin Feige and Clark Gregg confirmed that Gregg's Agent Coulson character - famously killed off in "The Avengers" - is coming back for the pilot of the "S.H.I.E.L.D." TV series.
At this point, no one knows in what form his appearance will be (he could just be there for flashbacks, for example) but Gregg was already joking about LMDs (Life Model Decoys, human-duplicate robots typically used to fake deaths in the comics and referenced in "Avengers" by Tony Stark) at the announcement. I seriously doubt that he'll be popping back into full-human existance (remember, Gregg is also a filmmaker in his own right so I'd be surprised if he committed to a TV series) but having a Coulson-based LMD - or maybe some kind of "digitized memories" hologram or computer-presence - onhand as part of the team would be a clever way of keeping him around while also keeping him dead "for real." It would also leave the door open for the popular fan theory of Coulson becoming the Movie-verse version of The Vision (short version: He's a Terminator who dresses like a superhero and has the digitzed memories and personality of a dead good guy.)