I've been with my wife for 10 years.....married for about 3. We have always had separate accounts that our pay gets deposited into. Every 6 months to 1 year or so we will sit down together and go over all expenses and what we each bring in. Its split up according to percentage........She pays for our child, I pay for the house.
Cars and Student Loans are up to the individual as well as any incurred credit card debt.
We keep a joint checking for paying the bills and a joint savings that we contribute to every month for Vacations or what not.
We have common short term financial goals such as debt free in 3 years...house paid off in 8. Mid-term goals.....Son through college....buying additional properties. In fact the only place where we differ is long term goals but that's a different thread....
Bottom line........I honestly don't think it matters much as long as you communicate properly