The W650 is a reissue of the Kawa W1 and W2 from the sixties. Those bikes were replicas, as well as the rest of japanese bikes of the era, of the british bikes. The "Black Bomber" was the first "big bike" that should have warned the british industry about what was coming from Japan, though it was still very similar to the british bikes. The CB750 was the real McCoy, completely original, well designed, reliable and cheaper than their british competitors.
I love the new classic Triumphs, the W650, the Eddie Lawson Replica, all of them. I don't see anything wrong with it. Like in dressing, styles comes and go. When "retro" becomes fashion, definitely it gives you more credit if you use an original item, not a replica.
But don't forget that there is a modern day CB750. When the retro craze started in the 90's, and Kawa launched the Zephyr as a replica of the Z1, Honda launched the CB Seven Fifty as a replica of the CB750. I posted about it a while ago...
Raul