It's one of the hottest questions around, but whatever William and Kate name their first-born, it will likely set a trend for the next generation of babies.
And on choosing the name for their new arrival, the royal couple will take the opportunity to pay tribute to those nearest and dearest to them, so long as it is a name that befits the future monarch.
William and Kate have plenty of names to draw on - members of the Royal Family often have three other names in addition to their Christian names: William Arthur Philip Louis is the Duke of Cambridge's full name.
At the end of an extraordinary few years for the Royal Family which have included celebrations surrounding the Diamond Jubilee and concern about the health of the monarch and her husband Prince Philip, the names Elizabeth and Philip are obvious contenders.
"Since the pregnancy was announced Elizabeth has been the name on everyone's lips, but in recent weeks that momentum has shifted towards Alexandra (the Queen's middle name) and Charlotte," explained Jessica Bridge from bookmaker Ladbrokes.
"The largest bet placed on the market was £1,000 on Elizabeth by a punter in Northamptonshire. It's the biggest and most exciting novelty betting event in history, so it's not hard to imagine why people are parting with their hard-earned cash on the future King or Queen."
Diana and Frances (Diana, Princess of Wales' first and middle names) have been widely discussed. Frances was also the Duchess of Cambridge's great great great grandmother's name and Francis, her father's middle name. Frances was also the Christian name of Diana's mother, Frances Shand Kydd.
The Duke and Duchess will notify the Queen of their chosen names more as a matter of courtesy than for her approval.
"The Queen is so down to earth that she is not likely to jump up and down and insist the baby be called George or Charles," explains royal writer Christopher Warwick.
"This isn't going to be 'Granny, do you approve?' but more 'These are the names we've chosen, do you like them?'"
It hasn't always been such a relaxed affair. When the Duke and Duchess of York had their second daughter - Margaret Rose in 1930 - they were planning to call her Ann Margaret, but changed their mind after learning George V disliked the name Ann.
And Queen Victoria insisted that the name Albert be used as a middle name, if not a first name, in hour of her consort Prince Albert.
But the Queen has gone a step further when it comes to Kate and William's baby to ensure a baby girl be given a royal title on a par with that of a baby boy.
Thanks to a Letters Patent, Kate's bundle of joy will be called HRH Prince or Princess (name) of Cambridge. Without it, a baby girl would have been given the title Lady rather than Princess.
Royal baby names are not always revealed straight away often leaving the public to guess for days. It took a week to announce William's name and a whole month before the public found out the Prince of Wales would be Christened Charles.
There is no hard and fast rule over how quickly William and Kate will name their baby, but after Kensington Palace revealed the couple chose not to find out its gender beforehand, a choice of name may take a little longer than expected.
And whether boy or girl, thanks to intervention by the Queen using a new Letters Patent, the new-born will be a Prince or Princess and carry the tittle Cambridge, like it's parents.