Tempo blogged about some other player's method for memorizing the board. Then he tried to solve a Polgar brick puzzle by looking at a blank board. He was just curious. In the comments he sums up the same sentiment BDK has with regard to memorizing the board:
board vision in itself is only interesting if you want to play without a board. Which I don't. In a real game there is a real board, so there is no need for perfectboard vision. (allthough it is fun in itself)
Which brings me to the next blogger who blogged about this topic. BDK blogged about the uselessness of memorzing the color of squares which he thinks is even more useless than memorzing the board.
I'm probably never going to memorize the board proactively. If I memorize it as a result of looking at the board so much, so be it, but I'm not going to take the time to memorize it. I think at my level, there are far too many other tasks I can focus on right now that will give me a better ROI than memorizing squares.