Is it wrong that the first thing that came to my mind when I read this was "You no pay-a the tax, you no make-a the rules"?
As someone of Sicilian heritage, that made me chuckle a bit. I actually think it's funny.
As for the Catholic Church being taxed by the Italian government, I have to say good for the government to finally have the balls and stand up to this monolithic entity. I think that this will probably, in the future prompt other governments to do the same with the religious institutions in their countries.
I do believe in separation of church and state but that to me, is only dividing the ideologies and prevent the government and the church to rule over one or the other, such as teaching intelligent design in a public school, prayer mandates in government jobs, etc. However, I do feel that churches should be taxed. Especially now since most churches, particularly megachurches run as corporations and/or political platforms. There are plenty of churches and religious organizations out there that should have their tax exempt *cough* Scientology *cough* yanked from underneath them.