It may seem tempting to ignore the Next Block Window (by pressing the SELECT key) and try to go at the game blind. However, it severely hampers what strategy you can make, and you can rely only on intuition and chance. Besides, you do not get an extra points with the window deleted; therefore it can only help, not impair.
For those of you with the Flash plug-in: I was going to have the theme from 2001: A Space Odyssey play in the background, but it multiplied the file size. So, just hum the opening bars of Richard Wagner's Thus Spake Zarathustra in your head or something.