The WP7.5 RC3/Tango’s new build 8779 which we reported to be available for 610 and 710 is now available for Lumia 800 and Lumia 900 as well. In case of Lumia 800 it is available for both RM-801 and RM-819 variants, while in case of Lumia 900 it is available for global version RM-823 only. Also in case of Lumia 800, only Vietnam and Thailand firmwares are available while for Lumia 900 firmwares for many countries are available.
The availability of firmwares for all four Lumia devices hints about a possible release soon 🙂
Changelog for 8779 is not known, but according to “blogosphere” it seems to bring few changes like “Location icon” to your device and may be some bug fixes.