http://nobelprize.org/nobel_prizes/physics/laureates/2008/phyadv08.pdf

It is not easy to read with so many physicists' terminologies. But I would like to try my best to understand what is "broken symmetries" about.

Finally, got time to read the whole article. I think the most interesting part is the last paragraph:

"To find the origin of this CP violation we probably have to go beyond the Standard Model. Such an extension should exist for other reasons as well. It is believed that at higher energies other sectors of particles, so heavy that the present day accelerators have been unable to create them, will augment the model. It is natural that these particles will also cause CP violations and in the tumultuous universe just after the Big Bang these particles could have been created. These particles would have been part of the hot early universe and could have influenced it, by an as yet unknown mechanism, to be dominated by matter. Only future research will tell us if this picture is correct."