We pushed out a small official release (2.0.17) this morning. Immediate afterwards, we also released a new beta version (2.0.18) that includes full multisite support and other fixes.
The 2.0.18 includes:
*NEW: Full multisite support, including:
-- Fixed: "Browser doesn't have flash, silverlight..support" error
-- Fixed: Various upload issues on multisite instances
-- Fixed: Network settings and controls on multisite
-- Fixed: Removed reset / uninstall options from sub-blogs
-- Fixed: Various front-end errors on multisite
-- Other multisite fixes and improvements
*Fixed: Image quality is set to 100 by default
*Fixed: Backup images option not saving properly
*Fixed: Broken link in Overview admin page
If we can get a sense that these fixes improve performance on multisite instances while not introducing any new instabilities or issues, we'll release these fixes as part of our full public release next week.