The confession of Peter in Jesus is the same confession that the church is built on. That which stands behind Peter's confession, and enabled it, is that which stands behind ours. Nevertheless, this doesn't devalue the important role which Jesus gave to Peter in forming the Early Church. It is a comparative statement ... Peter IS the rock, the fondation, in the sense that he was the first to make the profession.
Also in the sense that he, Peter, was personally given the keys and the power to bind and loose on Earth, which decision would remain in Heaven. While we share St. Peter's confession, we do not possess the keys; not even the other 11 Apostles possessed the keys.