Same issue of motorcyclist that had their helmet analysis, they also had an interview of the PJ1 guy... He stated that WD-40 and kerosene will do a decent job of cleaning the chian, as all you need to accomplish is dissolve the old lube that is on there. They said the problem with Kerosene and WD-40 is that it leaves it's own residue on the chain. No surprize, but he recomended his own brand chain cleaner.
He said something interesting abou O-ring chains and chain wax. He mentioned how wax doesn't have a "memory". Once you compress wax, it tends to keep it's new formed shape. This is a problem, as the chain will compress the wax, and then be unlubricated for every thereafter revolution.
To the myth that you do not need to lube o-ring chains, o-ring chains trap the lubrication into the chain. However, you need to lubricate the o-rings themselves. This is why you should use a different lube than your old old chain lube. Make sure that it's o-ring safe. I personally use PJ1 blue lable, however, i've had good results with Maxima (the goldish labled one, called clear? i don't remember).
I also clean my chain with kerosene. It was $5 for a gallon at ace, and i've maybe used 1/5th of it, and i've had it for a year. I just pour it into a spray bottle, put the bike up on the rear stand, spin the wheel by hand, and spray.
I really want to try out Crystal Green... NASA folk use this stuff because supposidly it leaves no residue behind after cleaning...