The suggestion is actually made in the last part of the thread: use an output function. This is a function which you can define which is called at each generation. Then set options = gaoptimset('OutputFcns',@myfun); where @myfun is an anonymous function that uses your output function. It needs to have the structure defined here but it's pretty straightforward.
For instance, you could write an output function which displays the current level, or saves it to a file, or whatever. The information about the current state is here here. For instance, you could just write the function to do disp(state.Best) to accomplish what you want, but I'm sure you could get more creative.
