"We weren't expecting it," Seward told The Early Show co-anchor Julie Chen. "We thought that one day he would marry her, but we weren't expecting it quite so suddenly."
Seward, the editor of Majesty magazine, noted that Charles and Parker Bowles have been living together since before Princess Diana was killed. "And now," Seward observed, "Prince Charles has decided to make an honest woman of her which is…what Diana wanted.
"The very last year of Diana's life, she'd come to terms with Camilla, and she said, 'I wish Charles would make an honest woman of her.' And now, he has."
Seward added, ironically, "I'm not sure that Prince Charles ever would have made the step to get married if Diana were still alive. I just don't feel it somehow.
"That's why I was surprised, because he has everything that he could possibly need. He's looked after, he's cared for. Camilla is his hostess. Did he need to make the final step to marriage? Obviously, he did. I think if Diana was alive, he probably would haven't done so."
The sons of Charles and Diana, Prince Harry and Prince William, have issued a statement supporting their father's decision. This does not surprise Seward: "I remember not very long ago, William saying, 'You know, so what?' Most of his friends had step-parents.
"So it wasn't a great big deal. And they know that Camilla makes their dad happy and, in turn, that keeps dad off their back!" she said with a laugh.
London Daily Telegraph social columnist and Vanity Fair writer Victoria Mather took some shots at the royals on The Early Show.
She told co-anchor Harry Smith that her sources tell her Parker Bowles won't be wearing a white dress, which "is lucky, isn't it? She'd look like one of those great big bits of ice that that have just fallen off the Antarctic. Having one of those coming down the aisle wouldn't be a pretty sight."
Mather confirmed that Di's nickname for Parker Bowles at one point was "rottweiler," and added, "Prince Harry is alleged to have called her (Parker Bowles) 'the goat,' because he said she looked like one.
"But most of the English aristocracy look like good-looking horses. It's fine. To be honest, the question, really, is why they're getting married now? I don't think it has anything to do with Valentine's Day. Maybe she's having a baby!"
The main thing, says Mather, is that this gives Britons "closure. It is the end of the debate as to whether they are going to get married.
"It's a great love story. He's marrying an older woman. She's a 58-year-old bag."
CBS News Correspondent Elizabeth Palmer says she's been talking to people on the streets of London whose main reaction seems to be, "It's about time. This is something Charles should have done years ago."