When will my Nokia Lumia 800 get next OS update?

Nokia Lumia 800 can be upgraded to Operating System Windows 7.8 Mango. Hence, it is not possible to install the Windows 8 OS on this handset as the upgradation option for this handset is not available.

It's a bit disappointment for users, but Nokia have stopped this feature for Lumia 800 smartphone. And, they have made available the Windows 8 OS in their latest smartphones.

There is no offcial announcement for update from windows 7.8 to windows 8. Microsoft recently released the update for Nokia 800 from Windows 7.5 to windows 7.8. So wait for few months and update may be announced.

You can't update your Nokia Lumia 800. It uses Mango OS and you have option to update it to Tango OS (i.e) V 7.5 to V 7.8. Windows is not like Android and you don't need much updates. Android OS has more bugs comparing to Windows and so more updates were released for Android OS. Updating your phone won't increase your process speed. You can search for custom ROM instead of updates for your mobile.

Sorry members I am posting answer to my own question. All above who says that I can not upgrade my Windows 7 OS are wrong. Yes it is correct that I can't upgrade it to Windows 8 but Microsoft has clearly announced that it will release an update for users of Nokia Lumia 800 with some features of Windows 8 like resizable tiles, Bluetooth sharing support etc. Coincidentally I got update for my Nokia Lumia 800 with some reasonable features of Windows 8, the very next day, I posted this question. Currently my OS version is 7.10.8862.144.
So now it is available in India, the update to Mango OS with features from Windows 8. There may some delay due to different mobile operators will allow it for different times. Currently I am using Vodafone as my mobile career.