I don't think we'll see the forked penis, as that would in all likelihood preclude a rating that would allow a more general audience. However, as regards the canonicity of the forked penis:
Remember, as seen in "Amok Time", Vulcans do not discuss sexual matters with outsiders. I believe T'Pol was merely "exaggerating" (just as Spock did about the repair time necessary in TWOK) and attempting to avoid a discussion about the forked nature of the Vulcan penis. Her comment should not be read as a denial of the canonicity of forked Vulcan penises.
Samuel T. Cogley said:
Further complicating this issue is the Star Trek: Enterprise episode "The Single Entendre," in which Trip is giving a neural massage to T'Pol with his penis. Trip bemoans: "Sorry, my penis isn't forked like you are used to." T'Pol responds dryly: "That is an urban legend."
Remember, as seen in "Amok Time", Vulcans do not discuss sexual matters with outsiders. I believe T'Pol was merely "exaggerating" (just as Spock did about the repair time necessary in TWOK) and attempting to avoid a discussion about the forked nature of the Vulcan penis. Her comment should not be read as a denial of the canonicity of forked Vulcan penises.