Flashed WP 7.8 to my Lumia 800
I downloaded it using NaviFirm and flashed it using Nokia Care Suite (ROM# 059L7C2). This method deletes everything from phone so I backed up my pictures. I was afraid of bricking my phone but luckily nothing went wrong.
Previously I had no option to set Google as default search provider. Now I can choose Google. There are new ringtones in Nokia section. Bing can update your lock screen wallpaper. I expected a pre-installed Bluetooth file transfer app from Nokia but there is no such app. Hopefully, Nokia will release that app in store.
I learned that some users who installed other ROMs got Bluetooth file transfer app.