Hi Stéphane,
Je viens de finir d'importer les adresse depuis OpenAdresses sur la suisse romande.
I still belive that any import from OpenAddresses is *not* according to the rules of OpenStreetMap, as it is just derived from Google Maps.
I know OpenAddresses gives you the right to do with their data (more or less) whatever you want, but I'm not convinced that they really asked Google about that.
I tried to sing up to their webforum to ask this question, but the forum seams dead; my account was never activated.
Regards, Thomas