There's no doubt that Times Square is very different from when I lived there. Much cleaner and much safer now. That said; I miss some aspects of the Times Square of old. I miss the giant signs made out of lights - they've almost all been replaced by generic-looking, building-sized HD video boards, all showing uber high-res advertisement videos. I miss the local restaurants, all replaced by national chains.
Disneyfication is correct. However, I also know that the Times Square of my years looked like an eyesore to people who lived there and remembered it from the 50s, the 30s, etc. It's always changing, so we all have our preferred version.
Truth be told, Times Square was filthy and dangerous when I lived there. If you want to get an idea of what it was like, watch Night Shift. That's the New York of my time living there, at least through rose-colored glasses. That's what I do when I'm feeling nostalgic. When I need a reminder that Disneyfication isn't necessarily a bad thing, I watch Taxi Driver. It's a reminder of how rough and filthy Midtown really used to be.
That grittiness is still there, big time, but these days it is different in the theater district (Times Square area) - and that's not a bad thing. It's nice to be able to walk down the street and not always have to look over your shoulder.
*edit*
Here's a film made from when i lived there. This is the Times Square I don't miss at all.
http://www.youtube.com/watch?v=zYsfQV5EPYo