We started blogging our travels for these reasons:
1. As I plan our stops I'm sometimes rather frustrated by the lack of information about campgrounds. One thing I really like is candid photos of the campsites and facilities. Most of the time I find staged "glamor shots" or photos taken with family ("our dog at Yellowstone") types of photos. I decided that I'd do the kind of reviews I'd like to see.
2. It is a nice way to let interested friends know what we're up to.
3. After spending months researching fulltime budget concerns I came to appreciate those who had opened the door bit to their finances. I'm trying to return the favor or at least pass some of my information on for others who are now doing their own research.
Mostly, though, it's just for our own fun - a way to record our adventures. Our blog gets 100-200 visits a day and once in awhile we'll see over 500.