Symbian Belle is major software update for all Symbian anna devices viz (N8, E7, C7, E6, X7, C6-01, 500) which brings its performance and usability on par with other major OSes like Android, IOS. Check our article for a comparison of Belle with Android.
Nokia confirms on its official twitter account that N8 and other devices are now available in various regions with Symbian Belle firmware pre-installed.
Nokia also confirms shipping Belle pre installed N8 to India as well. Check the second tweet from Nokia,
i am from pakistan! when belle udate comes to nokia x7 in pakistan cause ovi suite 3.3 shows me no udates available!
You can check the status of update availability for your device here,
http://europe.nokia.com/find-products/nokia-belle-update/nokia-belle-update-availability
Nokia, when is it possible to update from Anna to Belle in Indonesia