I don't have a horse in either race, but I'm curious - Have any blind studies been done to determine if vinyl does indeed sound better? My audiophile father-in-law would tell you HD-CD sounds better than vinyl, but I don't have the ears to tell either way...
Yes. These are from my days of reading high-end hi-fi magazines that don't have the content online, so I don't have links, but one of the more definitive double blind studies proved that people who claimed they preferred the LP sound over CD (including both "golden ear" audiophiles and professional sound people) indeed were able to reliably identify and prefer the LP sound in controlled double blind experiments. But, when the same experiment compared with CD-R recorded from LP as source, they were not able to identify the difference at all. CD-R from LP as source was equally preferred over CD as LP.
This corresponds exactly with the science of the technical characteristics of the two technologies, signal theory and human hearing. The "warm, analogue" LP sound carried perfectly over to the CD-R, as it is distortion characteristics of LP playback that CD is perfectly able to replicate (Nyquist theorem).
HDCD is a different discussion. I was myself a HDCD supporter in my (luckily now behind me) audiophile days. But HDCD mainly sounded better because the mastering was better, not because of technical specs of the format. HDCD productions took greater care with quality of mastering, not at least avoiding the overuse of dynamic compression.