It's undoubtedly a publicity stunt to make the monarchy seem more accessible, but the Royal Family will allow their personal family photos to be published to Flickr, and people will be allowed to use them. (Lewd and poorly 'shopped pictures of me and Prince William and Prince Harry! Yay!)
To this day, people are still obsessed with the wedding of Prince Charles to Lady Diana, so I'm sure this has been a popular hangout for those interested in the jetsetting lives of the figureheads. Zing.
There's not much of interest in the wedding photos, but it's kind of fun to look through the older ones to see how style has changed. I always forget how beautiful the Queen was.