Sociable and the Share This icon

It seems that the sociable plug in will allow you to show an alternate image like the share this image.

but I don't know if it works properly that way. Can anyone enlighten me about this? I actually wanted to use the share this widget, but it was too complicated and couldn't get it to work correctly or maybe it was that I could only find the image and not the actual widget/plugin. sorry can't remember now.

Thanks
Laura Simmons