I ordered a laptop computer intended for a Christmas present on 12/21/08. It was shipped by 2nd day air on 12/22. So far so good.
On 12/23, I checked the tracking number, and found that shipping had been rescheduled and would likely arrive by 12/26. (Though there is no guarantee of even that.)
I called UPS and asked for the reason for the delay. They said they had no idea. I requested a refund or adjustment, since I had paid for 2nd day air service. The representative said UPS does not do refunds. A supervisor gave the same answer, in a bland and bored tone of voice.
This is not the first time I've had problems with UPS. Three times before, they have lost packages I sent or ordered, which were shipped using UPS; left packages on a doorstep in the rain that required a signature, without obtaining one; and shown gross incompetence when asked to explain the reason for the losses and delays and other problems. Getting a refund from this company is a grueling, near-impossible task.
Based on these experiences, I'm recommending to every individual and businessperson I know, to look around for alternative shippers, and avoid using UPS.