I used to regularly cross the Atlantic on 747s, now I regularly cross in an SST. Believe me, the difference is enormous in contradiction of the above.
The reason that there will not be an airliner successor to the Conc is twofold: As already stated, the market will not support enough machines to make a viable manufacturing case. Secondly - the problem of noise in T/O and landing phases. Chapter 111 is barely achievable, 1V would be impossible.
I agree that the next civil SST will be a bizjet for both these reasons.