We build and maintain GIS data in a production environment with SDE on SQL 2008. We also have a need to open up WMS and WFS that will make a complete ESRI solution really expensive. With an ArcGIS Server Enterprise Advanced license, is it possible to replicate the data into a non-SDE postgis database and push deltas from the production environment?
You could use GeoServer to provide WMS/WFS direct from the SDE store. http://docs.codehaus.org/display/GEOTDOC/ArcSDE+DataStore