They have each of them established themselves as fully-fledged personalities in their own right, and there is every reason to expect that, as a duo, they will be a focal point of attention and a force for good in their public lives and service for a long time to come.
And then there is the additional intrigue generated by the coming together of two quite different worlds – the staid decorum of the royal family, secure in its centuries-old service to the British people and state, and the brasher, "anything goes" flavour of American showbiz.
Much of the commentary will no doubt reflect these aspects of the union, with attention lingering over the national, social, cultural and ethnic differences in the family backgrounds of the prince and his bride.
The infusion of these new elements into the life of the British royal family will be welcomed by many as a shot in the arm for the ancient institution and as providing an insight for the British establishment into the realities of modern life.
In the midst of so much public attention, however, it is surely important not to lose sight of a much more telling – and more private – reality.
The wedding is just that – a wedding – no more no less, the commitment made voluntarily to each other by two young people who have fallen in love and want to spend the rest of their lives together.
Whatever the public attention that the event inevitably generates, it is that private commitment that is at the heart of the day's celebrations.
We can all applaud the determination of Harry and Meghan to cross and set at naught whatever barriers might have been thought to lie in their way.
As the Roman poet Virgil said: "Love conquers all", and that is surely the theme of the day.
As we celebrate with them, we should also expect similar outcomes whenever differences are assumed to preclude couples, families and peoples from achieving harmony, closer relations and mutual understanding.
The next time we are told that others must be kept at a distance because they are different and not "one of us", we should remember this day and the commitment that Harry and Meghan have made to each other.
For the sake of their life together, they have each had to be prepared to move beyond the familiar, to set aside their initial expectations and to widen their horizons.
And, perhaps most importantly, they have restated their belief in the institution of marriage.
Nothing demands more by way of subordinating the self than the commitment to give one's life to another.
It is not always an easy thing to do.
It is so often the failure to act on that commitment that leads to disappointment, failure and recrimination.
But, if that commitment is made, and acted upon, the benefits to the people concerned, to their families and offspring, and to the whole of society, are enormous.
We will celebrate the royal wedding and are entitled to do so – not just because it is a glamorous fairy tale – but because it offers us a very public statement of the commitment made by two young people to each other.
The only difference between them and any other couple on their wedding day is that their celebration is to be conducted in the glare of international publicity.
Our congratulations and best wishes are, I believe, an entirely appropriate response.
Here's to the happy couple!