I won't pretend to be an expert, but here's what I know.
As you may recall, CD players went on sale in the U.S. in 1983. The
technology was jointly developed by Sony and Philips. This means that the
CD music standard as we know it today was developed more than two decades
ago. A key design issue, sampling rate, was limited by constraints related
to the chips that were available then. Basically, traditional CDs contain
no musical information above 20kHz (which after all is high above the range
of human hearing). *However* there is a great deal of musical information
(harmonics, overtones) that, while outside the range of hearing,
nevertheless impacts on the aural experience. So, conventional CDs hit a
"brick wall" at twenty thousand cycles, which is why some people still
prefer the vinyl format. A good analog pressing captures lots more musical
information; however the dynamic range - the difference between the loudest
passage and quietest passage is limited compared to a digital source. And,
of course, CDs eliminate pops and clicks, don't wear out (in theory anyway)
So, yes, DVD Audio represents yet *another* standard that will address the
basic issue of limited sampling rate. You may remember that, in the 1980s,
the industry expected CDs to appeal only to an audiophile audience.
However, the format was quickly embraced by the general public, prices for
hardware came down, discs became widely available, etc. Hard to tell with
the new format, which will (of course) require you to buy a new player to
realize the benefits. I don't know the exact specs of DVD Audio, but the
upper frequencies are captured better.
That's the story as I understand it.