Very Skrully, edition 3
Where was Maria Hill before Nick Fury got the boot, and how come I don't remember her at SHIELD? How convenient that she would rise to power just as Bendis begin planting the seeds of his Skrully storyline.
She's confusing, inconsistent, and just dangerous enough to put heroes in peril but never really seeming to kill them. She essentially forced Captain America underground, and she stokes the fascist flame of Tony Stark.
So using her behavior coupled with her ranking and rise to power she seems like an extremely likely candidate. Plus Nick Fury must figure big into the plans of the Skrull storyline, being as Bendis has announced his return somewhere between New Avengers 32 - 37.
But, then again, maybe she's the obvious choice. Her personality is so Skrully that she might just be an uptight human...
Very Skrully, edition 1
Very Skrully, edition 2