Interesting stuff from these german psychologists in the 20's. Seems really adavanced for the time in certain ways.
Some of the stuff seems kind of basic though like if something doesn't look like the things around it then it stands out, this seems like a basic thing any fool would know.
Some of the otheer principles are more interesting like peoples tendencies to see what they are familiar with in a design, even though it is just a group of shapes we may see it as whatever we are fmailiar with. This is interesting because 2 people seeing the same design may interpret it completely differently.
I did a little research online about the gestalt principles and I particularly liked the figure ground principles. I thought some of the most interesting desgns were in this category at the bottom of the page.
http://graphicdesign.spokanefalls.edu/tutorials/process/gestaltprinciples/gestaltprinc.htm