Looking at various tools & CX's own flight status info page, it looked like some sort of mechnical delay, plane has departed & airborne, arriving later this morning @ 11:20 AM SFO time.
Some CX fights to Taipei & Bejing were cancelled yesterday, might be related to the typhoon or storm (hurricane) that's going on oversea, disrupting air traffic too - and/or equipment needed to come in as backup for the regular aircraft assigned to that route. Mad & frustrated is understandable, but that's a fact of modern air travel and not much can be done at this moment. I'm sure your friend will got stories to tell upon landing - including whether or not all the pax. got any compensation, etc. or just an apology & sleepness night at the airport waiting for the flight to clear for takeoff.
When these long haul flight get major delayed for whatever reasons, it has ripple effect on schedules for other flights assigned to this aircraft / route, so it is not fun for CX to do this either & I'm sure they've done their best.
(EDIT - Notes: checking further, it looked like several HKG-SFO in-bound/out-bound flights had been delayed with 48 hours window and part of it weather-related, flights from/to YVR and JFK weren't affected - as I'm watching them myself as my group of 8 will be flying out in less than 2 weeks. Patience & calm will do a world of good, don't worry & be happy ! .... Friend's incoming flight is on its final descent/approach to SFO now and on the ground shortly)
Last edited by Letitride3c; Sep 4, 10 at 8:49 am.