When the Holy Father took possession of the Lateran Basilica, he said that it was not for the Pope to teach anything of his own but to pass on the Tradition of the Church. There has been a lot of tosh in the secular press about the Pope "changing" the teaching of the Church, or even abandoning a teaching, well that is not in the Pope's competence to do this. He is servant, not master of the Church, as Pope Benedict has continually pointed out. So it will be interesting to see his reaction to the work of the International Theological Commission who will report to him on "Limbo" today.
It therefor seems a bit cheap to suggest as Ruth Gledhill did in the Times that the Pope might be influenced to follow a Muslim line that all children go to Heaven, she should know one thing about Pope Benedict: he does not follow fashion.
The "Penny" Catechism, published by the CTS until recently taught that unbaptised children went to Limbo, so too the American Baltimore Catechism. The Pope's beloved Augustine taught that they went to Hell, where they endured punishment which was slightly less than everyone else's there. Peter Abelard seems to have "invented" Limbo, coming from the word for "edge" as in edge of Hell, a place of natural happiness, but out of sight of the Beatific Vision.
I don't think any Council has taught about Limbo, and has certainly not excommunicated those who do not believe in it, then I cannot think of anyone who has disputed it until recently. In the Orthodox Church the unbaptised either go to heaven or hell, depending on where or when, or to whom one addresses the question. Some might suggest that they go to the part of Hell that Christ emptied of the prophets and patriarchs at his "Descent into Hell" and because this event happened outside of time they are immediately redeemed, following them into Heaven.
I think the most the Pope can do is to say God is infinitely merciful, it is not His nature to create anything in order to condemn it or to destroy it, rather he intends that all creation should be saved. As far as the unbaptised are concerned, we must trust in his infinite mercy and love. The problem that we have in the West comes from Dante's image of heaven and hell that is graduated, all those circles, Scripture does not give us that, we are either in one or the other. Both Pope John-Paul II and the then Cardinal Ratzinger have suggested Limbo is simply theological speculation.
What he would not want to do is the encourage the delay or neglect of infant baptism.
There is a good article on BBC website