It's 2008, just because you knock up your girlfriend doesn't mean you run to the alter like you are being chased by a baptist group.
The whole 'promising' they'll get married thing just rubs me wrong. It's like, "Don't worry, I know they're having a baby out of wedlock, but they
will get married like they're supposed to." In this day and age, the welfare of the child should be the most important thing, not whether Mommy and Daddy are married. (In real life,) I'm more concerned about whether Bob and Sally raise their kid right than whether they do it with a marriage license.
(That's not to insult marriage, I just don't think getting or staying married 'for the sake of the children' is a good excuse. Get married because you want to and it's the right choice for your relationship - if it's not the right choice, the
children could end up suffering for it.)