I've read both good and bad things about upscaling SD content to HD. (I'm talking about the method used by Blu-ray and DVD players) Some say that it will definitely improve the picture quality, others say that it doesn't and yet others say that it will even worsen the picture quality. So what? Personally upscaled DVDs look sharper to me, but also grainier. Everyone probably sees this from a different perspective, so I'm asking: Are there any technical reasons why upscaled DVDs are better, the same or worse than non upscaled DVDs?