I just really - to put it in a Cable Forum non-swear filter way - don't care about the wedding.
I've never met the happy couple and chances are I never will. I hope they have a great day.
But...I think the BBC are doing something like 10+ hours of coverage on it - overkill much? They reckon 1 in 3 people within the UK will be watching, personally, I reckon it will be closer to 1 in 10.
ITV are doing coverage too and they can't show adverts during their coverage - poor buggers. As the Guardian points out, you've already got supermarkets etc doing tacky Royal Wedding products so what harm ITV doing a pizza commercial during their wedding coverage?
You've got Freeview hoping that the wedding will encourage people to go out and buy Freeview HD boxes - I'd save their advertising money for the Olympics myself.
In short, I reckon people will get

at the over-hyping of this event and fancy watching something off VOD.