It's a big Holiday in Sweden, basically like Christmas, but other end of they Year..
Actually, we don't give each other presents, but except that, I don't think there's any major difference.
All of it having to do with us, up here, having the year in 2 halves. One dark and cold, the other bright and warm, which is reflected in our mood. Someone visiting Sweden once in the summer, and then in the winter, I doubt would think it's the same country. In the winter, we tend to be introvert, walking around bracing ourself from the cold, and having a severe lack of sunlight. Introvert. In the summer tho, because of the loooong winter, we become kinda extremely extrovert instead. It's warm, even if it's only 13¡ C here now (You have to convert it yourself, if you want) and it seems to gonna start rain any minute. Then, it's only dark for like 2-3 hrs in the middle of the night.
Basic Midsummer Eve celebrating. First they raise a leaf-decorated Midsummer pole, the kids dance around it and play games. There's eating. In the evening, the adults dance and get drunk.
Not that much different from how we celebrate Christmas.. (which we, here in Sweden, celebrate Christmas Eve rather than Christmas Day, when we have a Christmas Tree, the kids dance and play around it, then we eat (much of it being the same food), but there's no adults dancing afterwards, I think, even if they have a drink or two and gets drunk.. lol