Xiaomi has decided to keep to it's promise by finally releasing announcing the third and final batch of xiaomi smartphones that will be receiving the MIUI 9 update.

Although the current update is still in beta stage, official and more stable update is set to start rolling out by next month October.
Xiaomi initially announced early this year that most of it's devices will be getting the MIUI 9 update which is based on Android 7 Nougat.
The update is splitted into 3 batches. Xiaomi Mi 6 and Redmi Note 4 were the first to receive the update followed by a second wave of devices such as Mi Mix, Mi Note 2, Mi 5, Mi Max 2 and a couple of others.

Below is the complete list of Xiaomi smartphones that can now be upgraded to MIUI 9 Global Beta
Mi 5
Mi Max (32GB)
Mi 2/2S
Mi 4
Mi Note
Mi 4i
Redmi 3
Redmi 3S/3X
Redmi 2
Redmi Note 3 (Snapdragon)
Redmi Note 3 Special Edition
Redmi 4G
Redmi Note 2
Mi Max Prime
Redmi Note 4
Redmi Note 4G
Mi Note 2
Mi 5s and Mi 5s Plus

Aside of this global release, Xiaomi also announced the release of the third batch of MIUI 9 China Beta ROM for following low-end and mid range smartphones: Mi Note, Mi 4 Mi 3, Mi 2/2S, Mi Pad 3, Mi Pad 2, Mi Pad 1, Redmi Pro, Redmi Note 4X MTK, Redmi Note 4, Redmi 4A, Redmi 4 Prime, Redmi 4, Redmi 3S/3X, Redmi Note 3, Redmi Note 2, Redmi Note 4G, Redmi Note, Redmi 3, Redmi 2A, Redmi 2, Redmi 1S, and Redmi 1.

Xiaomi MIUI 9 Global Beta Update Download Link
For all eligible xiaomi smartphones, you can download the update from this link and flash it via flashboot.