Google just released the official Android KitKat 4.4, and like the other versions of Android, the first question is whether your device get Android KitKat update or not? In the following we add the devices to get Android KitKat 4.4 on the list, based on the official statements of manufacturers.

Update 1 at November 2nd: Google, Motorola, and HTC are the companies officially announced their update schedule.
Update 2: Sony officially announced the list of Xperia devices to get Android 4.4
Update 3: Google updated some Nexus devices to KitKat
Update 4: Huawei announced the availability of KitKat for Ascend P6
Update 5: Motorola added more devices in the list of Android 4.4 update
Update 6: All 4 U.S. major carriers updated their respective Moto X to Android 4.4 KitKat
Update 7: The HTC One Google Play edition is now updating to Android 4.4
Update 8: Galaxy S4 Google Play edition is also receiving the update
Update 9: HTC USA rolled out the Android 4.4 for both unlocked and developer edition of HTC One
Update 10: Koran LG G2 owners are now receiving the OTA KitKat update
Update 11: Samsung is rolling out Android 4.4.2 KitKat for the international version of Galaxy Note 3, starting from Poland. No details about when other markets/carriers will receive the update.
Update 12: LG Saudi Arabia, via their Twitter account, officially announces the availability of Android KitKat for LG G2, starting from the end the month.  So, we can conclude that the global and wider roll out shouldn't be that far and other markets/carriers should be waiting for the update to hit their devices sometime in mid Q1 2014.
Update 12.1: Oops! LG Mobile Saudi Arabia seems to have sent a wrong info, as they announced the update is not about Android KitKat and is just about "upgrading the KnockOn feature to Lii series". So, if you own an LG G2 handset, you may have to wait a little longer, or more than a little, as some sources are suggesting end of the March for the KitKat rolling out date.

Google
Nexus 5 is the only device running KitKat at the moment and Google plans to update the following devices in the coming weeks: Nexus 4, Nexus 7 (we assume both generations), and Nexus 10
Update: Google updated the Wi-Fi versions of Nexus7s and Nexus 10 to Android 4.4 and you need to check the device update menu to see if it is available for you or not.
Update: The OTA update for Nexus 4 has been started.
Update: Google started the Android 4.4 update for the Google Play edition of HTC One
Update: The OTA update is now available for the Galaxy S4 Google Play Edition

HTC
The first HTC device to get Android KitKat 4.4 is HTC One Google Edition which is expected to get the update as soon as other Nexus devices. The Developer edition of HTC One is the next HTC device to run Android 4.4 within 30 days and the other HTC One devices, including U.S. carrier locked devices, will be update within 90 days. There is no detail or schedule about other HTC devices like HTC One mini and HTC One Max.
Update: The U.S. unlocked HTC One and the U.S. developer edition HTC One are now getting the Android 4.4 OTA. According the @HTCUSA you should be receiving the update notification today

Samsung
Samsung has not yet specified any update plan and the only device to get Android KitKat is Galaxy S4 Google Edition. While GS4 GE gets the update in the next few weeks, we have no time table for Samsung flagships: Galaxy S4 and Galaxy Note 3.

Motorola
DROID Maxx, DROID Ultra, DROID Mini and the Moto X are 4 Motorola devices to update to latest Android version. There is no promised date for the update release and we just know Motorola is going to update these devices in the future (we hope near future).
Update: DROID RAZR M, DROID RAZR HD, DROID RAZR MAXX HD, ATRIX HD and U.S. Cellular's ELECTRIFY M are the next Motorola device to received the Android 4.4 update with unknown update schedule.
Update: AT&T, Verizon, Sprint, and T-Mobile have all made the Android 4.4 available for Moto X, and you should get the OTA update notification in any time.

Sony
Xperia Z, Xperia ZL, Xperia Tablet Z, Xperia Z Ultra and Xperia Z1 owners are lucky enough to update their device to Android 4.4 officially. Sony didn't specify any roll-out schedule and all we know is that, it is not going to happen any time sooner than mid-December and the availability may vary by the carrier and the country (market).

Huawei
Ascend P6 is the first Huawei device to get the Android 4.4 Kitkat. According to their official post in Baidu, the device will get the update in January 2014.

LG
After numerous rumors about the decision of LG for not updating its best device yet, finally Korean customers received the OTA update for the LG G2 and now they can enjoy the features of Android 4.4 KitKat on their device. There are also some rumors pointing at the end of the March as the update time for the Canadian G2.