No. With WillMaker, each of you must make your own will, even if you both agree about how your property is to be distributed. There is solid legal reasoning behind this rule. Joint wills are intended to prevent the surviving spouse from changing his or her mind about what to do with the property after the first spouse dies. The practical effect is to tie up the property for years and make it impossible for the surviving spouse to react to changed circumstances. Also, many court battles are fought over whether the surviving spouse can revoke any part of the joint will. That’s why joint wills are very uncommon these days. If you want to restrict how your property can be used after your death, or make special provisions for children from a prior marriage, using a trust is usually a better solution. See a lawyer to set up this kind of trust.
That said, with WillMaker you and your spouse can easily create identical wills -- that is, two separate wills in which all the provisions (such as beneficiaries and children's guardians) are the same. If you want to do this, look for the "Duplicate for Spouse" button provided on the Congratulations screen at the end of the will interview (after the Print Preview screen).