One thing that has not been mentioned is that you need to be invited in order to join. That's no big deal if you know someone who is on it. If you don't know anyone, you can pm me your name and email address and I will invite you.
I am doing some remodeling and pinterest has been a great place to keep the pictures of all the things I like and might want to use. For instance, when I was looking for a back splash for my kitchen I would comb the internet for ones that I like and then pin them so that I could find them later. Now I am doing the same thing for my master bath. You can have as many categories and you want and it really makes it easy to find what you need at the time you need it. It is out there for everyone to see so you would not want to put anything personal or private on it.