Michael Jackson's will (or at least one of them) was admitted to probate recently and is on several websites for those who care to view it. Having taken a look at it, there are a few things I noticed that brought a few genealogical lessons to mind.
Things might be left out of the will--either intentionally or by accident. Jackson dumped his estate into a trust and the trust was not recorded (probably doesn't have to be is my guess). Does your ancestor's estate mention what happened to everything? I can think of several ancestral estate settlements where the real estate is inventoried, but then never mentioned again. If I had not gone to the actual land records, I would never have known how it was disposed of.
Jackson appointed his mother as guardian and if she could not act, then Diana Ross. While our ancestors probably didn't nominate celebrities as guardians for their children, names of guardians can be huge clues. In most cases our ancestors who had guardians probably had a step-parent, parent, uncle, aunt, or grandparent as a guardian. There are always exceptions.
In the copy of Jackson's will, the names of the witnesses have been blanked out. Hopefully that didn't happen on a copy of your ancestor's will. Witnesses could be people your ancestor knew or just people who happened to be in town "on business" the same day and were willing to sign a document as a witness.
Jackson's will was filed shortly after his death. State statute usually stipulates the deadline for submitting a will to probate. Thirty days is typical and admission of a will to probate can help a genealogist estimate when an ancestor died.
I have a relative whose husband died around 2:00 in the morning. As soon as the courthouse opened that same morning, she was there filing the will for record. But that is another story entirely.