you all make good points, but in all honesty, a building that is aesthetically beautiful in itself, will remain beautiful regardless of its surroundings. the same goes for any park or beach.
will it be important that the two harmonize? certainly. will the two projects' identities become synonymous with one another? this is unknown. if one clearly outshines the other, it is highly possible that the project generating the most praise will be be continually identified by itself.
let's just hope they both turn out absolutely beautiful in their own rights, and that they both together become waterfront classics!