Went to the dealer yesterday and the salesperson said his first thought was that it could be the shipping blocks. Over came the technical guys who quickly dismissed that idea, insisting someone would have noticed when preparing the car for delivery. The technical manager then drove the car with me around town and remarked that it was "normal". Never mind extra panty cushion, this guy thought I needed huggies and a bib. He then checked tire pressures and informed me that the fronts had been inflated past recommended maximum, and this was the likely cause of vibration. He lowered all pressures to minimum. I remained dubious until I did my daily drive, which was much better. It's still not ideal, I may end up tinkering with things, but am much happier. Thanks to Ateam and others for your suggestions. The most irritating thing now is having to obey the speed limit.