Should I be able to use an element property for Image.Source?

The following does not seem to work, I'm getting an exception indicating "No Property of name Source found". The property GestureRecognizers works just fine.
This is on Xamarin.Forms 1.3.0.6284-pre3

Thanks!

                    <Image  Aspect="AspectFit">
                        <Image.Source>
                        <OnPlatform x:TypeArguments="FileImageSource"
                                                        iOS="about.png"
                                                        Android="ic_action_about.png"
                                                        WinPhone="Toolkit.Content/ApplicationBar.About.png" />
                        </Image.Source>
                        <Image.GestureRecognizers>
                            <TapGestureRecognizer Command="{Binding FlipCardCommand}" NumberOfTapsRequired="1" />
                        </Image.GestureRecognizers>
                    </Image>