How it compares?
>How does this technically impressive but inherently unstable layer
>cake compete against inexpensive, stable, and fast hard drives?
You think the first hard drives were big and stable? Or any other technology for that matter?
>Priced a BD disk recently?
Uh, yes. A 25GB BD goes for about $12 now, prices already dropped since last year's $20.
A BD has a shelf life of approximately 200 years, a HD doesn't get anywhere close and it's subject to mechanical failure.
As a professional photographer I rather burn a few coasters and have my photos safely backed up on several BD than several HDD.
You know, not everybody needs storage to save their illegally downloaded games, videos and music.