Joint accounts benefit you both, but if an account ever goes into default then creditors can pursue you both for the debt.
If you're in a community property state (Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, and Wisconsin), you might as well make all your accounts joint and reap the benefits. In a community property state, creditors can come after both of you and put adverse TLs on both of your credit reports should the account ever go into default, EVEN IF IT'S AN INDIVIDUAL ACCOUNT!