There are a couple of interesting wine events and tastings coming up in December. One is the Vignerons d'Europe, taking place in Montecatini Terme and Florence from December 5th through 7th.
Another is the 5th edition of the "Campionato di Vino" which unfortunately I can not fully explain. I believe it is actually some kind of taste off between participating wine makers. The link will take you to the Slow Food Firenze website.
I am looking forward to the "The Vignerons d'Europe Market" on Monday, December 7th in Piazza Santissima Annunziata (starting at 2 PM). This is where the wines of the participating "Vignerons" will be up for tasting and sale and the afternoon is open to the public for a small fee.
Below are links to a some relevant documents for these events: