HideoK on 02 June 2010
I own over 70 blu-ray movies and I haven't purchased a DVD since PS3 launched.
I remember once DVD came out I refused to watch VHS ever again. The difference was mind blowing. And ever since early 2008 with everything being released on blu-ray I reached the point where I refuse to watch a DVD ever again at home. The difference is so great between the two when you sit as close to an HDTV as I do (about 8-12 feet). DVD looks extremely soft and blurry by comparison.
I suppose if you sit 25-30 feet away it would be a bit harder to see the sharpness difference depending on how good your eyes are. But the huge improvement in colors with the increased bit-rate that blu-ray allows are another dead give away that I'm watching a blu-ray. 
