I was screaming for "Of Chaos and Eternal Night" the last tour, but I wouldn't mind them pulling out Shadow Duet during the show. Of course, they'd need more then a 5 song set to do that...
Here's hoping they come back as at least a direct support act (hour set or more).
Actually, my dream preformance is to see them play a set with Lacuna Coil and have Cristina come out and do the female parts in "A Bolt of Blazing Gold".