OK well firstly it’s worth pointing out that a wedding book is no longer a simple bound memory of your wedding with pictures and comments from the guests. In the new age of technology it can now be electronic, or even hosted online with various documents included. It could be a secure site (this is probably wise) with a password for people to use if they would like to browse it, but you could make it completely open to be viewed by anyone if you prefer.
Some people have what they call a wedding story book, its becoming a bit more popular at the moment and does tend to be the traditional bound type with pages and a cover as opposed to being electronic, but could be either. All they really are are a book with pictures digitally produced and actually printed on the pages, this is quite a clever use of modern digital photography technology, as a professional wedding photographer will use a digital camera anyway, so can just email the pictures over to a printer for production.
One benefit of having the book online is also the option to incorporate other media such as music and video, it’s extremely likely that you (or one of your guests) will have a video recorder and will film some of the key parts of the day, such as the ceremony, if they allow it in the church, the signing, the speeches and possibly the wedding band. Just remember that unless a particular speech was very good, then nobody is going to sit through half an hour of groom, father and best mans speeches, so best just keep it to the highlights if you want people to make it all the way through.
Many couples will have a party band playing live at the wedding instead of just a disco, so with their permission you can probably either record the wedding band or ask them for a professionally made recording of a couple of songs they play (a suggestion would be your first dance song) to have playing over the static photographs, this would bring the whole thing together nicely as your guests are likely to remember that was your first dance, especially if it’s a fairly well known song anyway. Most wedding bands are likely to oblige, after all, they may even get some more work from it one day.
So if you are planning on having a wedding book, make sure you get the wedding photos electronically and get the bands permission to use their music, the rest can all be done once you get back from the honeymoon.