No argument, it looks slightly better. But again, it would not make me a happier human to watch it in blu. The dvd's I have are SO much better than the VHS's I used to have, they look great to me. This reminds me of research I saw video of, re. happiness. You give babies a mobile with three items, they like it. Give them five items, they like that too. Now step them back down to three and see what happens. I'm happy with my three-item mobile. It is WAY better than the one-item (b&w UHF) I grew up on. (Which made me happy at the time, by the way.)
I guess what I don't understand in all of this "DVDs are good enough" stuff is why wouldn't you want the best presentation you can get (the closest we're going to get for the foreseeable future to having your own pristine 35mm copy of each episode)?
I've owned TOS on VHS and DVD too, and watched plenty of syndicated repeats on TVs new and old. Including a little B&W TV in my grandparents basement. All of which made me happy at the time too.
As I said, the clarity, color, and contrast of the Blu-ray release is unparalleled, so I've never looked back.