Hi Glen,
The Open ODS layer can be considered as the successor of the Data Acquisition layer. For persistent storage an aDSO with field-based modeling should be used here (instead of PSA in a scenario with ODP). Next to the persistent storage, also Open ODS Views can be used. An Open ODS View enables virtual access to externally managed data.
The EDW Core will offer the EDW services which we know from classic LSA. Here you can find aDSOs in both Corporate Memory layer (probably field-based) and Propagation layer (InfoObject-based).
Best regards,
Sander