Now this is excellent. I'd been told on Friday that my iMac had arrived at a warehouse too late to be sent out to me, and would be sent out today. So I waited until midday and it hadn't come. I checked the TNT tracking page again, this time the non-international page which had said "out for delivery" earlier in the day, now showed "please call" again. The international tracking page couldn't find the consignment.
So then I had to go out to uni, and left someone else to deal with it. The first call confirmed that it was in the warehouse on Friday, but was still in the warehouse. They promised to phone back, but they didn't and when we phoned back spun some rubbish about not realising they had to. They then said that it hadn't arrived in the warehouse until Saturday.
A subsequent broken promise to call back with more information, and it turns out that it's not in the local depot after all, but in Southampton, which is about 2 hours and a stretch of water away. Supposedly it will go on the van tomorrow around 8, which means that I can't expect it much before lunchtime. We never really got an explaination for it not being delivered today, but we were given an excuse that it had to be in the warehouse 24 hours (wtf?), and that it was Apple's fault because they had an agreement about delivering things more securely...