Where will it end up?
A Microsoft trademark for "Forzavista" was recently spotted by Siliconera. According to the United States Patent and Trademark Office listing, this is for "A feature of interactive video game software which allows players to obtain statistical information of internal and external features of a vehicle and to virtually navigate and operate those vehicles."
There is presumably another Forza on the way -- that's practically a given, at this point -- but what specific form the series will take next after Forza Horizon and whether or not this "Forzavista" feature will be incorporated remains to be seen. With any luck, we'll find out tomorrow during the Xbox event or, failing that, next month at E3.