I just booked a flight on UA844 September 8 TPE-SFO. I asked the agent if she had heard anything about it being cancelled permanently and she said no. I went ahead and booked it anyways. My TPE-SFO booking for July 1 got rebooked through NRT weeks ago, so we'll see when they rebook my Sep 8 flight.
I travel this route 4-5 times a year, so it is a big disappointment that it is going away. Although I last flew in before the SARS peak, I didn't notice load problems on any recent flights. In fact most were full. It is hard to believe the loads won't come back now that SARS is tailing off.