Santa is definitely Odin-ish, especially in aesthetics, but the "facts" cited in that comic are mostly nonsense, not tied to any primary sources of pre-Christian Norse beliefs. It was always explained to me, for instance (I was raised Swede-tinted Lutheran) that the custom of leaving straw in shoes was to fend off the Tomte (little gremlin-like gnome things with funny hats) not to ingratiate either Odin, Santa, or Jesus. The Tomte were their own thing. Which makes more sense, since gnomes are house spirits. If the straw is supposed to be for Sleipnir, why on earth would you leave it by the hearth? You'd want to put it out in the stables, yeah? If it's inside, Sleipnir will have to come inside to get it. You don't want that. He's the size of a house, and he's got eight razor sharp hooves. This is a recipe for disaster. I guarantee you, if that flesh-eating half-horse half-centipede monstrosity gets inside the house somehow, there will be no festivities this year.
Do they really not teach anything about Norse culture in European schools? I thought it was just us.