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The largest change - the 'system' table that holds all your device data (IP, name, manufacturer, model, et al) is now called the 'devices' table. Much more intuitive and something I've been meaning to do for years. For those upgrading - your queries, summaries, and widgets (et al) will be upgraded as best we can. I would suggest checking any self-created items to ensure they work as intended. Also for upgraders, we have implemented a 'view' in the database named 'system' which should function as the system table did before and enable a (relatively) painless transition. That view will not exist for new installs. 
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Changed Collections
We have removed a few items that were surplus to needs and to be frank, creating unnecessary complexity. Buildings, Floors, Rooms, and Rows are all gone. Those attributes were used only by the Racks collection and the attributes are now stored directly in the Racks table. When you create a new rack you can select an existing building, floor, room, and row or create a new one. Your existing data will populate the racks table as you would expect. 
The data for Baselines Results is now stored in the database, just like a regular collection.
Removed URLs
All web requests now go to /open-audit/index.php/$collection. Previously we had that URL for Community and /omk/open-audit/$collection for Enterprise. The latter has now been removed. You will need to update any of your own links. 
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Any existing licenses for Professional, Enterprise, and Collectors are automatically imported. 
The data for Baselines Results is now stored in the database, just like a regular collection.
The GUI has nice new shiny buttons. There is now an option (per user) to display the buttons with an icon and text, just an icon or just text. The icons are colored consistently. Blue for read-only, Green for read/write of data, and Red for removing data. Oh, and there are a couple of yellow/orange icons for warnings. This makes sense to me. 
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