It's said that laughter is the best medicine. It's also an important and useful tool for building an audience for your blog. Writing with humor will improve your writing and is more likely to attract readers.
There's a fine line between being funny and being offensive. The first will make people more likely to share your blog with their friends and visit your site again in the future, while the second will upset your audience and drive them away. Know the audience you are writing for, and know what lines should not be crossed.