What's wrong with this?

gistfile1.json

{
    "activity": {
        "actor": {
            "name": "Jim Martin",
            "email": "[email protected]"
        },
        "action": "yammermvc:publish",
        "object": {
            "url": "https://dox.com/file/abc123.pdf",
            "description": "A set of charts showing the ROI of deploying Yammer over time.",
            "video": {
                "width": 1,
                "height": 1
            },
            "type": "yammermvc:photo",
            "title": "Yammer ROI.pdf",
            "image": "https://dox.com/file/abc123.pdf"
        },
        "private": "false",
        "message": "This is the updated version for the conference.",
        "users": [
            {
                "name": "Brian Davis",
                "email": "[email protected]"
            }
        ]
    }
}