OK, so here is what is happening at 9.3 with ArcSDE.

  1. ArcSDE finally rides into the sunset. Even though technically ArcSDE has been replaced at 9.2, it was still a separate product. Now at 9.3 it will become fully integrated into ArcGIS Server. ArcGIS Server Enterprise will be the “traditional” ArcSDE level where ArcGIS Server supports an unlimited number of users via either direct connect or connection to an application server. It offers DBMS support for IBM DB2, IBM Informix, all editions of Microsoft SQL Server, Oracle and PostgreSQL. It has no data or memory limits. The Workgroup level of ArcGIS Server supports a maximum of 10 direct connect users. It includes an embedded DBMS (Microsoft SQL Server Express Spatial). It has a data limit of 4 GB and a memory limit of 1 GB.
  2. ArcGIS will connect to Microsoft SQL Server via direct connect. Out of the box ArcGIS application will be able to connect to Microsoft SQL Server Express Spatial, but if you want unlimited users, you’ll need to purchase ArcGIS Server Enterprise. This is probably less than what folks wanted, but you’ll have to sort that our yourselves.
  3. ArcGIS supports older versions of the Geodatabase. At 9.3, ArcGIS can connect and create geodatabases (personal, file) back to 9.0. This means you won’t need to keep older versions of the geodatabase around to share with others. You also won’t have to upgrade your geodatabases just because ArcGIS went to a new release. If you wish, you can keep your older geodatabases running at whatever release you wish (back to 9.0).
  4. SQL Server 2008 Spatial will be fully supported when Microsoft releases final version of SQL Server 2008. This might mean that SQL Server 2008 support might not show up until SP1 or SP2 for 9.3. It all depends on Microsoft’s release schedule.
  5. PostgreSQL support will be available at 9.3 as has been reported. There will be support for both the PostGIS and ESRI data types.
  6. ArcGIS Engine will allow developing with Microsoft SQL Server 2008 Express so you can scale down your enterprise applications to the workgroup level. You’ll no longer be limited to working with personal for file geodatabases.
  7. ArcGIS Server Enterprise will support 64bit processors. This is only the spatial database application server and not the AGS Basic, Standard and Advanced product.

So does that answer your questions about ESRI spatial database support at 9.3?