Stories about possible developments in the Roman Catholic view of Limbo have been running in the media lately. For example:
"Father Brian Harrison, a theologian, told the BBC News website that while limbo may have been a 'hypothesis', he argues that the clear 'doctrine of the Catholic Church for two millennia has been that wherever the souls of such infants do go, they definitely don't go to heaven'. He argues that this is borne out in the various funeral rites for unbaptised children practised by the Church. 'A papal decree reversing the firm Catholic belief of two millennia that infants dying unbaptised do not go to heaven would be like an earthquake in the structure of Catholic theology and belief,' he said." (BBC News)
"'All of us have hope for the babies' that they will go to heaven, under the revised thinking on limbo, said the Rev. Luis Ladaria, a Jesuit who is secretary-general of the Vatican's International Theological Commission....Asked if the document will 'tip the balance in the favor of heaven' for babies now believed to go to limbo, Archbishop Bruno Forte told state TV, 'I hope so.'" (The Associated Press)
I recommend reading some of the stories that are circulating, since they reflect some of the thinking that's going into the decisions being made, and they reflect the sort of cultural influence that often shapes Roman Catholic theology. However, keep in mind that many of the sources reporting on this subject in the media are significantly ignorant of Roman Catholicism or are opposed to what that denomination teaches. Mainstream media sources often are unreliable in what they report about religion, including Roman Catholicism in particular.
I believe in universal infant salvation, and I'm a credobaptist. I reject the concept that unbaptized infants would go somewhere other than Heaven, and I reject the concept that Limbo is a teaching held by the Christian church for two thousand years. One of the reasons why I believe in universal infant salvation is because it was a widely held belief among the earliest church fathers, including fathers from a wide variety of backgrounds, dispositions, and locations. For those who are interested, I have an article on infant salvation here. And I have articles here, here, here, and here, for example, arguing that the earliest Christians didn't practice infant baptism. Those who are interested can search the archives of this blog for my interactions on this subject with Paul Owen earlier this year.
It should also be noted that the term "Heaven" is often defined in different ways by different people. I'm using the term in the general sense of a realm of positive attributes (peace, joy, etc.) near to God. There can be different places or phases within it, such as Hades or the New Jerusalem, but all of the places and phases collectively are "Heaven" in my use of the term. Though some of the early patristic sources may have had something like the heavenly region of Hades in view when they referred to infants going to be in a positive place in the afterlife, I'm not aware of any reason to conclude that they had something like Limbo in mind. It seems that the infants would go to the same sort of heavenly region of Hades that non-infant believers would go to.