I'm a little bit skeptical, to say the least. Cardinal Ratzinger is reported to have twice handed in his resignation as Prefect for the Congregation of the Doctrine of the Faith, "only to be asked by the Pope to stay on" (source). I can't lay claim to inside sources from the Vatican, but I suspect that if the Cardinal had his druthers, he'd like to retire in peace, spending his waning years writing theology texts, playing the piano, enjoying the solitude of the Bavarian Alps.
Meanwhile, the Cardinal had previously given his preference that the next Pope "be from Africa", which was interpreted as a support for Cardinal Arinze. Who, I agree, would also be ideal given his firsthand experience dealing with Islam, the liturgy (he currently heads Congregation for Divine Worship and the Discipline of the Sacraments) and interreligious relations (former head of Pontifical Council for Interreligious Dialogue) -- good experience to have, especially in this era.
If called to serve the Church in yet another capacity, I'm sure Ratzinger would be up to the task, and I'd personally be delighted by the election of either Cardinal to the office, but I try not to speculate too much. I trust the Holy Spirit to guide our Cardinals in their decision.
Hat tip: Bill Cork.
- "Who's Your Papa?", good commentary from Fr. Stephen Hamilton ("Catholic Ragemonkey") on this.