Is the MOSS Business Data Catalog required?
No. The Business Data Catalog, or BDC, is used when connecting SharePoint with an underlying data store, to display entity information using SharePoint lists. BTRG’s Connector integrates PeopleSoft’s existing UI into SharePoint, so the BDC isn’t necessary. To be clear: this product doesn’t only connect to PeopleSoft data — rather, it connects to PeopleSoft UI, but displays it in SharePoint.