My response to that question is usually "where to start". While he covers the high points of what is wrong and how to fix them, I'm afraid that the only people listening are the people who look at those lists and shudder.

However, in the interet of giving a balanced view, the 72 hour recommendation while obsolete and optimistic isn't a horrible one. From 72 hours to 120 or more, so long as you have appropriate clothing and have been able to salvage it, and a shelter, the only difference really starts to be how much water and food to stash.