It’s official: Meet the Duke and Duchess of Cambridge

"It's official!" my colleague Zachary Roth reports from London:

A smiling Prince William and Kate Middleton were moments ago declared man and wife at London's Westminster Abbey, in front of a congregation of around 1,900 and a worldwide television audience estimated at as many as 2 billion.

Wearing an ivory and white satin dress designed by Sarah Burton--a closely guarded secret until minutes before the service began--Kate accepted a wedding ring of Welsh gold, given to William by the Queen soon after the couple were engaged. The bride also wore a halo diamond tiara loaned by the Queen, with her gently curled hair down at the back.

In a marriage ceremony led by Archbishop of Canterbury Rowan Williams, Kate promised William that she would "love him, comfort him, honor him, and keep him," and he offered the same pledge. Like William's mother Princess Diana at her own 1981 wedding to Prince Charles, Kate struck a modern note by omitting the traditional vow to "obey" her husband.

William, 28, who chose not to wear a ring, donned a bright red tunic, with a crimson and gold sash and gold sword slings, from the Irish National Guards, a British Army regiment of which he is an honorary colonel. The choice was made in part to honor three members of the Guards who were killed in action in Afghanistan.

The bride's ring was created by Wartski, a Palace spokesperson said, a family jeweler that also created the wedding bands for Prince Charles's 2005 marriage to Camilla Parker Bowles, now the Duchess of Cornwall.

Kate, 29, the daughter of creators of a successful party-planning business, becomes the first commoner in line to be queen in modern times. She'll now be known officially as Her Royal Highness the Duchess of Cambridge, Buckingham Palace said in a statement this morning--though the public will know her as Princess Catherine. William becomes the Duke of Cambridge. ...

After the service, the newlyweds rode to Buckingham Palace in a horse-drawn carriage for an intimate lunch with some 650 guests hosted by the Queen.

(While millions of onlookers enjoyed the newlyweds' kiss at Buckingham Palace, a certain someone (left) seemed to be not pleased.: AP Photo/Matt Dunham.)