After Ramadhan is definitely the celebration. What we celebrate may differ greatly. Some celebrate because they now can eat as usual and can party to their hearts content. Some celebrate because this is the time of the year they can show off their new house, their new decorations and whatever they can show to people that come to visit. Some celebrate by throwing big open houses so that people can remember until next year how grand their open house is. They outdo each other in showing their "generosity".
Talking about generosity, some people have good intentions of giving to the unfortunates, but the way it is done is more like wanting to let it be known to the whole world. They forget that it is best that the hands that received do not know the hands that gave. So, the culture has developed that it has to be a grand ceremony when giving to the poor, the orphans and the unfortunate.
However there are a lot more out there that celebrate the end of Ramadhan by saying a prayer or two for having the time to appreciate the great month. A time to be thankful for the good life that they had and a time to repent.