I think some ought to be a little more polite and less critical here.
Let's examine some things:
It is a holiday weekend and planned cancellations are normal.
Due to the unusual nature of this flight: the length, CO's infrequent service to HKG, the unique service this flight provides to New York, and the distinctive flight path; this flight draws more than just a passing interest for an aviation enthusiast. For CO, these things might contribute to a feeling of pride and prestige. I would logically conclude that this flight would almost never cancel due to the above reasons. There is nothing strange about that.
I disagree with the statement that flights cancel all the time and that's typical. Just because mainline cancellations happen does not make them common under normal operational days (meanining no blizzards or other unusual circumstances). For example, on a normal day Continental boasts that they usually complete around 98-99% of their mainline flights. 100% completion days are not rare or unheard of. I have been out to my local airport, Denver, 4 times the last few weeks. Each time I carefully look at UA's departure and arrival screens. Among all their hundreds of flights, not once did I see a mainline flight cancel (commuter flights? that's a different story). Therefore I conclude UA is about the same. Two years ago I took a flight on UA. It's a long story, but the flight was 7 hours late and not cancelled. I have had nothing unusual happen since then on any trips. The point is that airlines try to avoid cancelling flights at all costs, especially international long hauls. So those of you who claim cancellations are "common," please use some operational statistics to define what you mean by "common."