In photos it seems like minimalism is white and black designer furniture. I argue that this isn't very minimal. Minimalism is something that's inside of you. In the same way that GTD is about emptying your mind, minimalism is about minimizing the effect of the outside world on your inner mind.
Expensive designer furniture may reduce the effect of your busy environment, but it will also increase the worry for the moment that you drop a cup of coffee on its white fabric.