Soon the European Data Portal and the EU Open Data Portal are coming together to offer regional, national, EU and international data in one space: data.europa.eu. Stay tuned for more details.
Update: DCAT-AP advancements
Developments in the field of DCAT-Application Profiles (DCAT-AP) for Open Data portals in Europe are crucial for enabling cross-data portal search for datasets and making public sector data better searchable across borders and sectors.
Italy's national repository of territorial data RNDT published the "GeoDCAT-AP implementation Italian guidelines". This type of Data Catalogue Vocabulary (DCAT) can be considered a national extension of the GeoDCAT-AP and takes into account the Italian extensions to the INSPIRE metadata profile and the DCAT-AP. The published specifications help to bridge the categorisation of spatial data from the RNDT and the Open Data from the Italian national Open Data catalogue dati.gov.it.