I checked the tracking page this morning and saw that they were out for delivery, so I relaxed and played some TF2 while I waited. A few hours later I checked again and saw that they had been delivered. They were signed for by R. Grove, which is odd, because R. Grove had been sitting on his ass for the past three hours pwning bitches.
Naturally, I called FedEx to ask them where they had delivered my expensive new speakers. They put me on hold for a few minutes, then told me they'd ask the driver when he got back this evening, and then they'd get back to me by Tuesday. Couldn't they just ask the driver now and save some time? No, they couldn't. Surely, if the driver is capable of transmitting the signature to the website electronically, there must also be some way of contacting the driver while he's out and about? No. Apparently not. But "don't worry," said the FedEx support agent, "this isn't the first time something like this has happened."
Clearly, FedEx has incompetence down to a science, so I should sit back and allow them to do what they do best. In the meantime, if you happen to have taken delivery of a couple of fancy speakers that you didn't order, could you hold onto them for me? Thanks.
Update: At around 5pm, the FedEx guy showed up at my door with my speakers. It turns out someone else on his route had ordered the same speakers from Woot, but in a different color. Since they were in almost identical boxes, he accidentally delivered my speakers to that guy (which is where the strange signature came from). He eventually realized his mistake, swapped out the speakers, and got everything sorted out.
Talk about a funny coincidence.