Silica uses femtosecond lasers for writing and supposedly mostly ordinary silicate glass as the medium. This would probably mean more costly drives and severely cheaper media (Folio claims $3/TB now, $1/TB eventually. I wager Silica would be at least 10x cheaper). If Silica keeps its promises, we might be looking at archival prices cratering. But it's been in development for over a decade, I wouldn't hold my breath.
Really interesting would be R/W speeds.