From what I can tell, the currencies Primecoin (XPM) and Peercoin (PPC) are very similar; both use the same proof-of-stake system, and hence have the same inflation rate. The main difference seems to be Primecoin's use of
Cunningham chains for its proof-of-work. I want to ask some questions about this.
If there are no other differences, then what is the point of Peercoin today? Will Peercoin still be relevant in the future?
Exactly how useful are the scientific contributions made by Primecoin?