Have you looked through your December magazines yet? In just about every one that I get (and I get a lot of them), there is a recommendation for a specialty cocktail syrup of one flavor or another as a suggestion for gifting.
By the time I noticed this, I'd already written my latest story for Details.com, which we ended up calling Syrups are the New Bitters. It's not to say that you no longer need bitters now that there are more syrups on the market, but rather where once there was a lack of variety of bitters on the market and bartenders turned into entrepreneurs to develop their own brands, now syrups are at that same place.
I mentioned many brands specializing in syrups dedicated to particular cocktails, seasonal syrups, and a whole section on tonic syrups.