I am not a trusts and estate attorney. But with some help from my friends, we've selected one to prepare our family's estate plan, which really consists of preparing our wills and educating us about the wills. As my wife put it, reading a draft will can be daunting. Our respective draft wills were over 40 pages.
I never really pondered how assets move upon the death of a spouse. However, because of some questions from my wife, we learned what happens to a dead spouse's assets.
Here is a graphic showing my understanding.
Updated on September 14, 2015 to add more details.