A personal blog is a site that personifies who you are as a person into a digital landscape.  It takes your thoughts, feelings, experiences, and interactions and makes them consumable to your reader base.  There are numerous personal blogs out that are considered a wild success.  They can also be vastly different from each other.  There are usually a couple of common factors that make these blogs a success.

They Have Their Own Voice
A successful personal blog has a voice that is unique and all his own.  He/she doesn't just spit words out on paper.  You can feel the words coming to life with the use of his/her arsenal of words and phrases that really let the reader know there is a real person behind the text.

They Are Personable
They speak in reference of individuals, not groups or communities.  They use phrases like "I", "Me", and "You".  Whenever personal bloggers write, they are speaking to an individual, not a general audience.  It is much more personal that way.

They Are Visually Stimulating
People are more than just text in a diary.  Those are the thoughts but pictures and video bring it to life.  A visually stimulating reading experience is much more memorable than just plain text alone.

They Share Real Life Experiences
It is not uncommon to see what a person's opinions, thoughts, and feelings are on a blog.  It's also not uncommon to see pictures of their family, friends, vacations, or what they had for dinner.  Experiences are about real life, not just words, and they can be brought to the blog with the sharing of these experiences with the readers.

Remember, your blog isn't just about making money, stepping on a soapbox, or spinning your wheels.  It is an extension of yourself.  The more you treat it that way, the more of a success it will be.