So is this tax in place now or not ?
Yes, it is and it has always been effective as of December 27th, the snag being that until recently there was no way anybody could actually pay what was due as the modes and terms of payment were not specified in the body of the law itself, as they never are. Now we know that an owner is supposed to "spontaneously" pay his dues either through his tax declaration (obviously applies only to Italian residents) or by means of a bank transfer to a public bank account (IBAN number provided).
How this is supposed to be enforced and who, if anyone, will actually be tasked with enforcing it is still the subject of speculation. Keep in mind that the tax is not due as soon as your wheels touch Italian soil, but only after 48 hours of uninterrupted stay, and tax authorities need to be able to prove it or charges won't stick. Read into that what you will...
Ciao,
DG800