No mention of 6TB support, speed improvements, or any new features.
I have installed it on 1 unit. Nothing to report at this time. I wouldn’t be surprised if the bug was happening to this unit. It has had some odd cases of going offline causing the backup system that is using it to do a lengthy corrupt data check. (not always sucessfull I should say, as there have been 2 occasions when we needed to restart the backups from scratch due to corrupt data)
There is also a new release of Drobo Dashboard today:
Drobo Firmware: Version 2.0.5 [3.44.72119]
This is a new release of Drobo firmware for both Drobo Elite and Drobo B800i.
• Fixed a rare crash of the Drobo device caused by heavy IO load when other transactions are running.
Drobo Dashboard: Version 2.6.6 
This is a new release of Drobo Dashboard for Windows hosts. Key highlights for this release are:
• Fixed: A Dashboard service crash reported in the field.
Yes, the 2.0.5 firmware update for the B800i did have many improvements for bug fixes, as well as better stability for the unit when under heavy loads of I/O. I would recommend updating to the latest firmware, and definitely keeping up to date on the Dashboard version as many improvements were made to the recent 2.6.5 and 2.6.6 releases.