Why are we (as Americans) so fascinated by the wedding of Prince William and Kate Middleton? A few reasons are obvious: the girlish love of princesses, our love of a good party, the spectacle and pomp and circumstance.
But I suspect that there is another, harder to reach reason for our fascination — one that is buried deep in the national psyche. In the United States, we have an equality fetish. The value of equality is at the very center of what is still a rigorously democratic national character. The typical American is convinced that no particular individual is any better than he is. Of course, this is not to say that the typical American believes that he is no better than anyone else. In our yearning for a perfect democratic life we are rather hypocritical — we look at those above us and say “Why should they be up there?? That’s unfair.”, but we look at those below us and say “Well, clearly I am the better man.” In other words, Americans have a nostalgia for an order in which it is not a secular sin to admit that someone might just be a better person than someone else.
Monarchy is a political philosophy that explicitly celebrates this truth that Americans cannot quite bring themselves to admit: Some people are just better. This is not to say that Prince Bill is ACTUALLY any better than the average “commoner,” but his position (Prince) makes the symbolic claim that there are better and worse people (and that these are inherent characteristics — not judgments that extend from your willful actions). Even though England is a great democracy, it is a society that still has a much more coherent idea of “class” than the U.S. (a country where “class” in the English sense is a concept that is under perpetual suspicion). That English society still goes through the motions with their royalty provides the public an outlet to indulge those anti-democratic fantasies.
Americans don’t have an outlet for those feelings (at least not an American outlet). So, vicariously participating in the gross display of superiority that was the royal wedding offers a bit of a reprieve from a society that cannot bring itself to recognize the better man. The American mythos is a beautiful thing in the way that it intertwines fairness and equality as if those concepts were of the same mother. If we think even for a moment, I believe most of us would admit that they are bitter enemies: most Americans maintain a secret knowledge that true equality is often unfair, and that fairness is often unequal. Royalty, stripped of its real political power, serves only a symbolic function: signifying that even in an age of savage equality, the better man (as an idea) lives on. Cheers to that, mate.
rhetoricaadnauseam 
I’d have to disagree about Americans not having an outlet for feudal wanking. Any major sports figure, Hollywood celebrity, pop star, TV sensation, hot author, charismatic politician, etc, can scratch that itch.
In fact, I’ll go even farther – corporate culture is feudal simply by virtue of having a top-down structure. As academics we are pretty much spoiled rotten by working in a relatively non-hierarchial organization of ‘peers’ – a word which has its historical connotations…
There is a hunger out there in humanity, Americans in particular, a hunger for the worship of merit that scares me. I have deep philosophical problems with admiring someone because they are skilled at something or powerful by virtue of birth or money. These aren’t essential human qualities to me.