Plane Tickets Purchased

We finally took the plunge, we bought the tickets with travelcuts last week. We found a one-way ticket to Shanghai from Toronto for 800$ and we decided it was too good a deal to pass up. Of course, after booking the tickets we started to panic cause the travel agent told us we might have trouble boarding with just a one-way ticket. It sounded ridiculous to us, but I guess it can cause trouble. We checked up message boards all over the place, and I checked the U.S State department website, which gives the entry requirements of every country. China, of course, does not require proof of onward travel, mainly because it requires a visa and charges about 800$ Can. for every day you overstay your visa. I think thats a little bit more insentive to get out of the country than the 400$ extra we would have shelled over for a return flight.
Oh well, we have a few contingency plans in case they hold us up at one of the many airports. We fly Toronto - Chicago, Chicago - Tokyo, Tokyo - Shanghai. Our layover in Chicago is 4 hours and Tokyo is 1 hour. Thats fine with us, since we figure the U.S customs are going to be more of a pain in the arse.
Anyways, we have the tickets and it makes us just that much more ready to get out of here!