EDIT: This method still isn’t working perfectly for people. I suggest trying the normal registration page, and then calling in to get your code if things are still failing. The US call center claimed that they can’t register new accounts over the phone.
As posted earlier, Atitalia is offering a status match to elite members of various other frequent flier programs.
Unfortunately, when I tried to register, I just repeatedly received a mysterious error “Error in Service.” There have been reports of the registration successfully completing even with this error, so check your email. I unfortunately did not get this email.