According to pureviewclub personal hand-on comparison, here's notable difference betw 808 & 1020:
1. 1020 actually has slightly smaller sensor size than 808.
2. F2.2 for 1020, F2.4 for 808
3. 1020 has BSI sensor for better low light imaging, and RGB sensor for better white balance. 808 has none of above.
4. 1020 has optical image stabiliser as earlier we mentioned.5. xenon flash also for 1020, but slightly smaller than 808's.
6. 1020 comes with better software to control the camera features.
7. NO 'Bracketing', 'interval shot', or 'Timer' features ? ( I guess we need confirmation on that.)
8. PHotos to shoot at Either 5MP or 34MP, no more 8MP pureview mode, which I used the most.
9. NO saving in Raw Format !
10. 6x zoom in 360p video format, 4x zoom in fullHD format.11. 1020 has lower minimal focusing distance than 808 it seems, but no details of how close it is.
12. 1020 has mechanical shutter.point no 4, a SECOND GENERATION OIS according to Juha (maybe better but i see no moving video samples yet)
point no 10, 360p will not be available but like 808 we can choose the framerate that we want (which is cool!) and the zoom is not at smooth as 808.