No really, it is. I mean, sometimes it's hard to find the humor. And I will admit that there are occasions where there may not be any humor, but most things are funny.
Not only do I like laughing and finding humor in otherwise icky situations, but I enjoy seriousness. When it's called for. I'm a "sensi," as JD would say (that's a Scrubs reference, people). I can be seriously serious to the point of moping/wallowing/laying around crying while watching Dr. Phil and eating a gallon of ice cream a day. So in order to avoid such horrid sights, I choose to laugh.
Mirth is good.
One of the things that really gets to me, especially amongst Christians, is the fear of laughter. God really does have a great sense of humor. I have seen the platypus. Not much makes me feel more full of joy and love than a good belly laugh. I highly suspect that heaven will be full of laughter, because it's awesome, and God created me to do it, and to love it.