I'm getting married to my partner in September and maybe I'm just odd, but to me the marriage part is what we've been focussing on, not the wedding (which could explain why I have absolutely nothing planned and would love to elope). I've read a number of books on the issue and we've done a fair few exercises together so that we feel completely comfortable that this is forever. One great one is "The 7 principles of making marriage work" as is the 7 Habits of highly effective families. As well as that we have a financial plan, goals for the next 5, 10 and 25 years and have the housework all divided up.
I think that the fact that we've lived together has helped because it gave us the chance to work through everything in preparation. For example, I am shocking at housework, but great at the financial stuff, grocery shopping & cooking, so we've divided it in a way that I handle all the bill-paying, investments, insurance, cooking etc whilst he takes over the bulk of the washing & cleaning. I then give him a monthly report on how everything is going and we have an education night at the same time so that he can learn more about why we picked a certain investment or how something is leading to one of our goals.
Given that I come from a Business background, as does he, I think we have approached it sort of like a business venture eg we each have a $100 limit and we have to ask the other if it's over that amount. It might seem cold to people, but I can honestly say that we've never had an argument about money, housework, health issues.