Frankly, Pinterest didn't seem very interesting at the first sight. Pictures are always beautiful but you can find the anywhere, why would you need another website just for that?
But it didn't took me so long to start to enjoy it. After some time I realised it became more important than checking facebook... And now after only one day it is sort of an addiction.
Although it seems messy and you don't understand from the very beggining what is your purpose there, slowly you begin to understand how it works and become part of the Pinterest "society".
As any other similar site, it slowly starts to take over your free time but I think that if you like it it doesn't matter whether or not you spend your free time online. It's a nice way of sharing nice stuff you find on the imense internet.
I the end, I'm happy I found this place and I tried it out.
Alice found her Wonderland! :) And is ready to explore it!