You are right, the "new" Dynaudios have been voice much closer to neutral (no longer have a "bloom"). They are smoother and much more controlled. However, I don't know that I fully agree that the tweeters are better than B&W. The new Dynaudio tweeters are very clear and clean. (The Op was asking about the Focus 600XD, which is the old Dynaudio sonic signature).
The B&W Diamond tweeters have a "bite" to the sound that kind of reaches out and grabs you. The "new" Dynaudio has a clearer and more solid sounding midrange than the B&W D2.
In my opinion, the B&W would have a much more exciting sound for HT, and I think it still sounds more "natural" than the new Dynaudio.. The "new" Dynaudio has a much more controlled and linear response, probably leaning more towards the Sonus Faber type of sound.
I think it depends on your tastes and what type of sound you're looking for.