I bought the Blu-Ray set a couple of months ago. I always thought the video on the 2001 DVD boxed set was too dark. The Blu-Ray set's color is more vivid, but it doesn't knock your socks off. Professional reviewers have commented that the BR version is truer to the theatrical releases, and were not intended as "spectaculars" to take full advantage of high definition.

The box says of the BR version, "In addition to the 2001 DVD Bonus Materials and provocative director's commentaries, this Godfather release contains these all-new Blu-Ray disc supplements:
Godfather World HD. The Masterpiece that almost wasn't HD. When the shooting stopped HD. Emulsional Rescue Revealing The Godfather HD. The Godfather on the Red Carpet HD. Four Short Films on The Godfather HD."

I haven't viewed any of these additions.