Nah, I don't really mess with standard definition anymore. I'm a renter, so, if it's offered in Blu-Ray I rent it in Blu-Ray. Maybe it's a buck more or something, but, it's never much.
The only time I actually do go for standard def is on an iPad or laptop, it downloads quick (nice when I'm on crappy hotel wireless) and want a lot of movies for a long flight or something.
In other news, many still buy standard def DVD.
Because there's not much blu ray porn yet.
Dude, there's a ton of blu-ray porn. Porn industry is generally super fast at adopting new technology. There was 3D porn not long after Avatar hehe. Also can thank porn for being on the forfront of a lot of the streaming technology today (NetFlix, AppleTV streaming...)
The armature stuff is even mostly professionally shot and then just made to 'look' armature. Since the cameras are so good now, generally the reduction is quality might even be done in post-process. I mean, a Canon 5D mk.ii for 2700 with a kit lens can shoot 1080p video (good enough even some episodes of House were filmed with it, obviously decked out, but still the same body). It's cheap to do high quality HD video now.
Then there are the high end shoots, which even Red One cams used (4096x2304 resolution, so, even Blu-Ray can't take advantage of the resolution), lighting, stylists, hair, makeup, grips, catering, fluffers (hehe).