It gives you the perfect excuse to stay in bundle up and catch up on your Netflix queue. Or go out and pretend your a kid again, build a snowman, make snow angels, and pelt the ones you love most with snowballs.
Personally, I prefer the best of both worlds. Nothing beats a snowy walk (or polar promenade, if you will) mixed with some cozy indoor time preferably with a warm beverage and a good story.
Whatever you decide to do with your snow day (be it honorary or official), be safe, stay warm, and have fun.
...just for fun: