Of course I'm willing to buy the expansion for HoH:S, too. I just singled out the two RoP books since I've noticed they generally prefer to tackle two supplements at a time, RoP:D and RoP:I naturally complement each other (like HoH:MC and TMRE), and IIRC the two RoP books hold rather more crunchy stuff than HoH:S (even if the latter has several new nifty Vritues and Flaws).
Oh yes. I'm a big fan of the software and the guys behind it (tireless dedication to the cause...).
But they have more than just the Ars world to support and only so many hours in the working week. I think they'll get around to it but it may take a little time.