I disagree with it "being a good sign". It is not a sign one way or another. Like Carey said, it probably depends on the center. Yes, the test itself takes less than an hour, but they do not necessarily run the test as soon as they collect the sample. For example, when my son was tested, the sweat tests were sceduled to be run at 2:00 pm. Since his sample was collected on a Monday at 3:00, they did not run his test until the next day, Tuesday. They called me with the results on Tuesdays. The same thing happened with his confirmation test. They collected his sample after 2:00 on Thursday and ran it on Friday with the other samples at 2:00. We got the final results the same day they RAN the test (not the same day the sample was collected), about an hour and 1/2 later.
Ask the lab when the sample is scheduled to be RAN. Then you know when to start making phone calls (your doctor will have to get the results from the lab as the lab won't give you the results... only your doctor).
GOOD LUCK!!