NBC viewership has been colossal for the Beijing Olympics, though my rosy estimates of earlier on on Internet's expected share of total viewings are off by a longshot. Here's a summary I found on TV Week:
The numbers for the web are impressive, but not colossal. Perhaps this is because the timing of events is basically overnight for the US, when we are asleep. And of course there is the fact that an event looks better on a 42 inch flatscreen than on a iPhone.
Thanks for reading, and don't forget to write.