I was pondering the three year deadline and remembering that after our fire in '03 there were some tax deadlines that came up at the three year mark. I went looking for them and found this in our Disaster Tax Issues handout which can be found in the "Tax Handout" section of our website. The first thing I found had to do with Property Taxes (page 12, slide 66): 

There are a lot of rules and calculations involved with determining whether or not you have to pay taxes on all or part of your insurance claim, so you need to take the handout to your CPA as soon as possible, but if you do have a gain and you want to reinvest the gain as opposed to paying taxes on it (page 7, slide 35):