Jambo was the original AKL hotel building and the fifth and sixth floors were redone as
DVC rooms in 2007. All the other floors remain Disney hotel rooms. Also the sixth floor exists only above the lobby and is the location of the DVC club level rooms (five 2BR lock-offs). The nearby Kidani building was added thereafter and completed in 2009. It is all DVC.
When you purchase, the contracts and deeds designate the building your unit is in (a unit is a combination of some rooms (not many). Besides the contracts/deeds designating the applicable building, when you reserve a room you also choose a building, i.e., you can either reserve a room in Jambo or a room in Kidani, and you are guaranteed being placed in the building chosen. Regardless of which building you are staying in, you can use the facilities (restaurants, pools, etc.) of both buildings.