For me, Far Cry 3 set the standard for open-world first person shooters and was far and away my favorite game of 2012. A big reason for that was its South Pacific islands and jungle setting - the second time the series has been set on and around a tropical island. Between those we got the African savanna. For Far Cry 4, if the now widely-reported rumors are to be believed, the Yeti will be far more at home than Jason Brody because the rumored location for Far Cry 4 is the Himalayan mountain range.
It makes perfect sense since it's another remote and sometimes war-torn region of the world replete with it's own native myths and legends.
It also has elephants. The rumors go on to state that elephants will be rideable. Not exactly what I'd call "fast-travel" but it is maybe "awesome-travel."
I just have one word for Ubisoft: Yeti. I love those stories and legends that revolve around Bigfoot and the Yeti and if Ubisoft doesn't give us at least one Yeti encounter - even one brought on by the liberal use of ingested "chemicals" - I will be very disappointed.
Right now, the word is that Far Cry 4 will be released during the first half of next year for the PC, PS4, and Xbox One.