China Transit Visa

I haven't been able to find a firm answer anywhere. In a couple of weeks I will be trying to get home from Tokyo. If those flights fill up, would it be possible for me to connect in PEK on a transit visa? At most airports I've been through I have to go out to the checkin counters to checkin so I figure I'm going to have to clear customs regardless. I've read that a confirmed ticket is required but also that a standby listing and airline ID should be ok. The flight has a ton of seats open so I'm not too concerned about not being able to get out on the flight and overstaying the 72 hours. I will have a visa shortly but unfortunately can't get down to SFO and turn in my paperwork before I leave for Tokyo!

edit: Thinking about it I could just have a standby listing and a confirmed for less refundable ticket for the following day just in case. It's only $500 so even if I get stuck and have to use that flight I'm not out a ridiculous amount.

I believe you would need a confirmed seat out of the country to do the transit visa thing. Without a visa or confirmed seat out you should not be allowed on the flights to China.