Title ownership matters. Even with the changes to the 2016 Illinois law. Its a common misconception that once you are married, half of everything each spouse owns belongs to the other spouse. As a result, people often see little harm in transferring a pre-marital asset titled in their own name into joint ownership. This can be a costly mistake in a later divorce. If you have a pre-marital asset that you kept titled in your own name, you have a strong claim that the property is your non-marital property which will be distributed to you in a divorce. While considered in divorces, non-marital property usually is not substantially offset by awards of marital property to the other spouse.
There is 2016 law that provides an exception if one can prove by clear and convincing evidence that the transfer was done for estate or tax planning purposes or for other reasons that establish that the transfer was not intended to be a gift. How these 2016 changes will play out is yet to be determined.