DVD is far from obsolete; it actually has some advantages over blu-ray for console gaming. For instance, a hard drive is pretty much mandatory for a ps3 due to much slower seek times. Notice, most ps3 games have madatory installs to navigate around the slow blu-ray seek times. I'm getting ready to laydown but I'm sure you can score some good game developer blogs about blu-ray seek times.
Granted, I love my blu-ray player (my PS3). Going forward I do hope DVD gets fazed out from consoles but look forward to seeing more mandatory game installs unless they figure out how to eliminate the slower seeks
Do installs really matter that much anyway? Drives go dirt cheap nowadays.👍