There’s an article on the All Points Blog that goes into more detail about the potential support for PostgreSQL/PosGIS in ESRI products. The caveats to this are listed below, and I have to ask- what’s the point guys?
It will only be in Enterprise ArcSDE- so you’ll need ArcGIS Server Enterprise Basic as a bare minimum, and of the windows products it will only work on Server 2000⁄2003. So- if you have loads of money to spend on your GIS you’ll be able to use PostGIS- but not if you don’t have thousands to spend.
It will contain it’s only spatial implementation alongside the PostGIS “spatial type”. So that will keep things clear and easy to follow then.
We had this debate ages ago, but it seems as if ESRI really haven’t listened. I guess it doesn’t matter that much to low-end users as there are alternatives but it seems like they are missing the boat. However apparently they are really interested in getting feedback at their non-existent forum so that’s OK…