I think it's the last physical media for music, at least for some time to come. SACD and DVD-A came and went (for the most part) and I don't see BD-Audio gaining much traction outside of a niche audiophile community.
We already see the clues with digital downloads slowly creeping up to overtake CD sales. Even with the vinyl anomaly right now, I see CD's dropping down to niche status within about 5 years, and vinyl/SACD/the rest not gaining much traction outside what's already occurred.
It's the reality of the situation -- I like physical media since it's not lossy in nature, but most consumers are quite happy with high-rate lossy files from Amazon or iTunes. And if they go lossless and high-res, that will be the final nail in the coffin for physical media for sure.
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