Adobe unveiled Adobe Experience Manager as a Cloud Service(AEMaaCS) on January 13, 2020. It was released mainly keeping assets and sites in mind. It combines the traditional AEM features with cloud agility. I have played around with it and gone through the documentation and here are some of the notable changes.
Brand New Architecture
AEMaaCS has a fully containerised operation. AEMaaCS further abstracts its hardware layer, taking care of dynamically scaling the infrastructure both vertically and horizontally when needed. Earlier, AEM needed a complex infrastructure with several servers that were expensive to support. I am not going into detail of the architecture as Adobe's documentation covers it pretty well.
Deployment and Upgrades
1. AEMaaCS is always up to date. Clients don't have to go through a painful process to upgrade their AEM servers.
2. Adobe Managed Services(AMS) now handles maintains maintenance on AEMaaCS. It is all automated. Tasks like data store garbage collection, version purges, compaction, audit purges etc are all managed by Adobe.
3. AEMaaCS has 24-hour point-in-time backup/restore which AMS handles.
4. AEMaaCS currently deployed on 3 Azure regions only.
5. Cloud Manager is now the sole mechanism for deploying code to AEM as a Cloud Service environments. It was an optional content delivery tool for Managed Services, when it was introduced earlier, but is now required. All content and code persisted in the immutable repository must be checked into git and deployed through Cloud Manager.