What Pinterest has done right is significantly change the way we interface with social media. By making posts picture-centric, we see ideas and concepts rather than have to read about them. In a mobile, portable media world dominated by tactile input methods (touch screens), this is an undeniable future.
This movement towards visualizing information is also typified by Instagram and Tumblr. You can point to the popularity of Facebook pics, Facebook’s new timeline interface, and Twitpics as further evidence. Finally the infographic movement towards visualizing data as opposed to blogging or writing about a topic is yet another bellwether towards pics instead of words.
Pinterest has value. In particular, for my client Razoo, which has a very strong female customer base. Of that I am sure, and so I participate on it because its my job to understand its strengths, good and bad.