A survey last fall showed that family law practitioners are handling more marital agreements (also known as prenuptial agreements) than they had in the past. Couples are apparently taking the time to assess their non-marital property and to plan their financial futures before they get married. Unfortunately, data for individual states wasn't available, so it's hard to know where Illinois falls.
We had a lively discussion this weekend about marital and non-marital property. A friend of ours was visiting Chicago from one of the prairie states, and after a few minutes of conversation she went into a panic. Not a breathing-in-a-paper bag panic, but definitely a wild-eyed "yikes" panic.