FB API response for page tab modification (console output)

gistfile1.js

FB.api('427939937270481/tabs/488588774508915', function (response) { console.log(response)})
    Object {data: Array[1], paging: Object}
        data: Array[1]
            0: Object
            application: Object
            id: "427939937270481/tabs/app_488588774508915"
            image_url: "http://photos-a.ak.fbcdn.net/photos-ak-snc7/v85006/87/488588774508915/app_10_488588774508915_117150173.gif"
            is_non_connection_landing_tab: false
            is_permanent: false
            link: "http://www.facebook.com/VidioJamie?sk=app_488588774508915"
            name: "vid.io (test)"
            position: 3
            length: 1
            paging: Object

FB.api('427939937270481/tabs/488588774508915', 'post', {custom_name: 'Videos'}, function (response) { console.log(response)})
    Object {error: Object}
    error: Object
        code: 210
        message: "(#210) Subject must be a page."
        type: "OAuthException"

FB.api('427939937270481/tabs/app_488588774508915', function (response) { console.log(response)})
    Object {data: Array[1], paging: Object}
        data: Array[1]
            0: Object
            application: Object
            id: "427939937270481/tabs/app_488588774508915"
            image_url: "http://photos-a.ak.fbcdn.net/photos-ak-snc7/v85006/87/488588774508915/app_10_488588774508915_117150173.gif"
            is_non_connection_landing_tab: false
            is_permanent: false
            link: "http://www.facebook.com/VidioJamie?sk=app_488588774508915"
            name: "vid.io (test)"
            position: 3
            length: 1
            paging: Object

FB.api('427939937270481/tabs/app_488588774508915', 'post', {custom_name: 'Videos'}, function (response) { console.log(response)})
    Object {error: Object}
        error: Object
        code: 210
        message: "(#210) Subject must be a page."
        type: "OAuthException"