The biggest thing I noticed is that, well, as far as I'm concerned, the show pretty much resembles the copycats that came out after Millionaire instead of Millionaire now. I'm not a fan of the questions being randomized. I think that bothers me more than any of the cosmetic changes would have.
The music I don't have too much a problem with after listening to it in action, both on the show and on the show's website when playing the online game. It's got a dramatic element; my TV speakers thumped like crazy to the sound of the question cues, particularly when the "heartbeat" part of the cues played.
I have my issues with the format changes, but Meredith is still at her best as a host. Over the years I've looked forward to seeing her emcee Millionaire, and from this aspect of it all, that hasn't changed one bit. She is still bringing her "A" game as far as I'm concerned.