Nothing new in Blu Ray audio. As Frans has put it, it is just plain old PCM much like DVD-Audio, in fact it even shares even the allowed sample rates (both disk types support up to 24/192 and multi-channel). BTW, these disks can be quite easily be ripped to a HD provided one has a BD drive in the computer, just the appropiate software would be necessary.
Digital Downloads make far more sense.
On the other hands, the "real" problem with "Pure Audio" releases so far is they have used very compressed remasters so, in a direct comparison, with a CD they will initially "sound better" but once levels are matched the older CD versions will sound in fact better in the long term as they have a much higher dynamic range. Nothing to do with the resolution but with the mastering and the loudness wars that started in the late 90s.
A typical example will be Supertramp's Breakfast in America:
This would be the DYnamic range of the original CD from the 80s:
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Analyzed: Supertramp / Breakfast In America
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DR Peak RMS Duration Track
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DR12 -0.78 dB -17.77 dB 5:20 01-Gone Hollywood
DR13 -0.23 dB -15.89 dB 4:11 02-The Logical Song
DR14 0.00 dB -16.57 dB 5:51 03-Goodbye Stranger
DR13 0.00 dB -15.37 dB 2:39 04-Breakfast In America
DR13 -0.15 dB -15.72 dB 3:49 05-Oh Darling
DR13 -0.73 dB -17.60 dB 5:09 06-Take The Long Way Home
DR13 0.00 dB -17.92 dB 4:10 07-Lord Is It Mine
DR12 -0.55 dB -15.53 dB 4:26 08-Just Another Nervous Wreck
DR12 -7.40 dB -22.03 dB 2:59 09-Casual Conversations
DR13 0.00 dB -15.65 dB 7:26 10-Child Of Vision
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The same album but from "Pure Audio" disk:
Analyzed: Supertramp / Breakfast In America [BD Audio]
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DR Peak RMS Duration Track
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DR9 -0.04 dB -13.16 dB 5:18 01-Gone Hollywood
DR9 -0.44 dB -11.95 dB 4:09 02-The Logical Song
DR10 -0.04 dB -12.75 dB 5:48 03-Goodbye Stranger
DR10 -0.10 dB -12.73 dB 2:38 04-Breakfast In America
DR10 -0.44 dB -12.56 dB 4:03 05-Oh Darling
DR9 -0.04 dB -12.31 dB 5:09 06-Take The Long Way Home
DR10 -0.05 dB -14.81 dB 4:06 07-Lord Is It Mine
DR9 -0.45 dB -12.35 dB 4:23 08-Just Another Nervous Wreck
DR11 -2.84 dB -17.15 dB 2:57 09-Casual Conservation
DR9 -0.03 dB -11.80 dB 7:27 10-Child Of Vision
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The difference is quite obvious and is the standard in the "Pure Audio" releases as can be checked in the
DR Database