This is just a must buy book every year, it is great reading whether you are a math person or just interested in math.
Honestly the description does not do this book justice, but I know they have only so much space.
The 2011 edition is almost the art and philosophy edition. Yes there is the article on Escher, but there are a few other articles addressing art as well ( Lorenz and Ribbon Sculptures ).
There are a few really great articles which are almost Poincare-type philosophical type essays ( really more Kant, but I never liked Kant ). And my personal favorite, mathematical models and the financial crisis.
I think every year they do a great job of selecting essays for this book.