By lack of a partner, Aliatalia does not see the need for a bigger airpplane at the moment than the 777. Future developments may lead to an additional order for larger aircraft, though at the moment they are not conidering this.
I think Alitalia will need bigger airplanes in the future but the choice will depend on their future partner. If Alitalia will join SkyTeam as I wish, they could express the need for a Very large aircraft in the form of the A380, even though they could afford only few of them.
Anyway, Alitalia has always been a strong customer for American industry so a 747-400LR order is not so weird.
Will the B744LR has commonality with the 777? If so Alitalia could bring a very good fleet based on the A320 family for short haul and on the 767/777/747 for the long haul earning in profitability from both families.