I have chosen this picture of a Venetian window framed in with fir twigs above bcause it captures the essence of what Christmas can also look like in Venice: How families decorate homes and facades.
In the public areas in town, in stores, restaurants and hotels you will find that Christmas in Venice is slowly adapting: Practically every hotel and most restaurants in Venice now have their Christmas tree. Here I would like to convey to you the true Christmas spirit that co-exists in Venice, one corner away from Natale sfavillante - the thousand glittering lights framing in Piazza San Marco like golden veils.
VIGILIA IN FAMIGLIA - Family Christmas Eve: Red Stelle di Natale, Presepio (Nativity Scene); Brodo di Pesce (Fish Soup), Pinsa (Venetian Christmas Eve Cake), Pandoro (Veneto Sweet Christmas Cake)
Christmas in a private home can be very different, though the Magia di Natale you find on the streets of Venice is rather contagious ... Every year, the number of Christmas trees in Venetian homes is rising - and who knows, there might be a tree in our home next year too ..
In the picture frame above you can see the "Christmas" arrangements at my grandmother's home, near Campo San Zaccaria, on Vigilia di Natale (Christmas Eve): There is a presepio (Nativity Scene) consisting of wooden figurine (figures), plus lots of small and taller bushes of Stella di Natale plants, which are Christmas presents brought in from neighbors and friends. 
Christmas Eve is called La Viglia di magra - it is a fasting day: Many people in Venice on that day don't eat dinner, including my grandmother. In the morning we have a sort of late brunch, consisting of freshly baked pinsa (a bread cake with raisins and dried fruit) and brodo di pesce (fish soup). There is a coffee and tea break afterwards, and in the evening we attend la Messa della Vigilia. For everyone who is hungry before, though, there is baccala e poenta or taleggio cheese, bread and cotognata (quince jam).  
Christmas Tree inside the Coin Venezia store
Of course things have changed - the restaurants in town offer marvelous dinner for La Vigila :-) All you need is turn round the corner towards the streets just behind Piazza San Marco, and you will find that all restaurants still have their tables and chairs outside on the calli, as always, ready to server dinner amidst the Stella di Natale bushes ...
Dinner amongst Stella di Natale - Christmas decorations in Calle Larga
And finally, you would like to take a look at Piazza San Marco on 24 December, turned into golden light by a thousand little light bulbs. Here I am standing a bit farther away, between the chairs of Caffé Quadri and Lavena. In the background you can see the Christmas Tree, almost reaching up towards the balustrade of the Basilica ...

Auguri di un sereno e felice Natale da Venezia - Happy Christmas from Venice !!