This one combines the best wishes for the new year with a christmas card. If you want to know why they are riding a pig (which is very German) you will have to watch the Glückschweinfilm I did for Arte…. Unfortunatly that one exists either in German or in French.
This was a work for Arte done in 2011. Karambolage is a TV show that is shown in Germany and in France and always explains customs of the other country. In this case it is about the Glücksschwein. In Germany for example small figurines of pigs are used as lucky charms. So if you want to wish somebody good luck you might give him a small pig made of marzipan as a present. The film explains the origins of this custom.