Wow, this thread is actually pretty encouraging (other than degenerating in the last few posts). I'm pleasantly surpised.
Congratulations, Katsarephat!
My thoughts in no way apply to everyone, but here's my two cents in case you find it helpful:
Don't approach the marriage as a 50/50 partnership. Your partner won't live up to your expectations, and in my experience this leads to keeping score and ultimately resentment. The counsellors my wife and I talked to before getting married told us that they have yet to see a marriage fail where BOTH partners approached the marriage as being 100% committed to the other person's happiness. Obviously, as humans, we aren't perfect and this doesn't happen all the time, but if you both approach the marriage this way, you cultivate a mindset that doesn't lead to resentment. You find yourself focusing on his/her happiness at the expense of your own, and are pleasantly surpised when you find him/her doing the same thing. Pre-marital counselling helped my wife and I avoid many pitfalls and learn good habits before we even got married. Many churches and pastors will offer pre-marital counselling at no charge.
<Broken Record> Communication is key! </Broken Record>
Bring things up that bother you and talk through them, but if it is trivial try to avoid bringing it up in the heat of the moment. Also approach the trivial stuff with the mindset of "How can I change my attitude?" rather than "How can I change my spouse?". If your partner is focused on your happiness they will be trying to change themselves as well, and in combination with you trying to change your attitude about something, you find that some issues just seem to disappear.
Also, I have yet to meet a couple that regretted waiting to have kids. It's easier once you've had a relationship with your partner for a few years to bring something into the relationship, rather than have kids to try to fix the relationship. The latter is a disservice to your kids if the relationship ends up in a bitter divorce. Once the kids grow up and leave the house, you'll have had experience living alone with the person you married, and you can avoid issues when the kids move out.
Also, finish any degrees you want to get before you have kids. Otherwise you miss those two-seven years of your kid's lives as you focus on getting your degree.
Oh, and ditto what fortknox said about inlaws.. My wife (and I for that matter) don't get along with her inlaws as well as we do with her parents. (Yeah, figure that one out!)
It causes some tension but the marriage is about you and your partner, not you and either of your parents. Good relationships with both help, but strained relationships can bring you both closer together. My wife's issues with my inlaws are teaching me how to avoid being like my dad.
Best of luck to you both!
+2 to the Stuki for correct usage of the plural! (one for each of you).