While we are big fans of Santa in real life, we have mixed feelings about Father Winter at our house. He does bring some cool gifts to most of the Sims in the household, but we've seen him ignore Toddlers, too. (Thanks for the suggestion about a way to fix that, @cornflake88 .) Clement can be a humorous sight when he's in his Santa attire, doing random Townie things.
On the other hand, he overstays his welcome...but that's a minor inconvenience compared to his other holiday "tradition."
Most of the time, Father Winter arrives in a flirtatious mood. He's spoiled more than one holiday by hitting on members of the household. He usually chooses someone who is involved in a relationship, as if his goal is to create as much drama as possible. He's fortunate one of my Sims hasn't chosen to deck more than the halls.