Beijing is 8 hours ahead of UTC, which in turn is 5 hours ahead of ET / 6 hours ahead of CT / 7 hours ahead of MT / 8 hours ahead of PT, 9 hours ahead of AKT and 10 hours ahead of HT. So for instance when it's midday in Beijing, it will be 4.00am in London, 1.00am in Washington, midnight (the previous day) in Austin, TX, 11.00pm (the previous day in Billings, MT, 10.00pm (the previous day) in San Francsico, CA, 9.00pm (the previous day) in Anchorage, AK and 8.00pm (the previous day) in Honolulu, HI.
This means that for the major primetime events (such as the Men's 100m) it will be shown at night in Beijing (about 9.30pm if Athens is any guide) which means that it will be shown at 9.30am ET / 8.30am CT / 7.30am MT / 6.30am PT / 5.30am AKT and 4.30am HT. As a result they will either show it as live (but with a 12 - 16 hour delay) or show highlights during the main US primetime slot.
I shouldn't worry too much though. Come Vancouver 2010, you should be able to watch everything live (as Vancouver is in the same timezone as LA) and London 2012 is only 5 - 10 hours ahead (depenedent on timezone).