John Bugay has lifted two interesting quotations from a recent book entitled, "The Petrine Ministry in the Early Patristic Tradition" (Eerdmans, Nov. 2010).
The first quotation includes "the monepiscopacy replaced presbyterial governance in Rome only in the mid-or late second century" from a Lutheran scholar.
The second quotation includes "The East never shared the Petrine theology as elaborated in the West. It never accepted that the protos in the universal church could claim to be the unique successor or vicar of Peter," from a Roman communion Archbishop.
Hopefully that whets your appetite for more! The context for the quotations can be found via the Amazon.com preview of the book, for those interested.