I used to play poker on www.holdempoker.com because it was Mac-friendly - I'm a happy owner of an iMac - and didn't require a separate client.
Unfortunately, since a few days the site has been acquired by Pokerroom.com, whose pages are unreachable from Italy because of the online gambling ban. Actually, as Holdempoker.com was not a well-known site, our government forgot to add it to the list of banned sites.
From a technical point of view, each Italian provider is forced to change the DNS entry of the websites included in the list, in order to replace it with the address of a Finance Department's page saying (in Italian) something like "We're sorry, the website you requested is not allowed to provide gambling services". Here's a screenshot of the notice.
Anyway, things may change in the near future: read this article from PokerNews.