I have a blog but only to track the development of my horse (I am retraining an ex steeplechaser to become an eventer). I find it a very good way to keep a diary of how he is doing plus it makes my mother (who lives in France) very happy!
I blog about everything (well lots of things) like running, training, riding and competition results usually come into it too. I don't compete often anyway and it's mainly so that family and friends from afar can see what i've been up to.
I tend to use ours for pictures only, as I'm cr** at uploading them any other method!
It does get sidetracked however with pics of my Christmas tree and cake, the dog and odd birthday party.. www.henryhorn.blogspot.com