I am in agreement with the water heater - no use in wasting energy if no one is there to use it
I also set the thermostat to heat and 60° in the cooler months and turn the AC to 76° in the warmer months - no frozen pipes in winter and a relatively temperate house in summer that doesn't take a day to cool down completely
I also turn off the water - don't want a leaking appliance (washer, ice maker, water heater, toilet) to leak for a week or longer. Plus, it keeps the dishonest neighbors from using my spigot for their sprinkler (no lie, the renters next door did that along with rummaged through my yard shed).
I turn off the circuit breakers to the outside outlets - again, don't mow your lawn or run your refrigerator with an extension cord on my juice!
Stop the mail - set the timers - leave a fluorescent light on in the kitchen over the sink - with closed blinds, it always looks like someone is in the kitchen (while the other lights go on and off randomly throughout the house). Leave at least 1 car in the driveway to make it look like someone might be there.
Don't order anything that might get delivered while you are gone, including checking your subscription items (Amazon, paper products, water delivery, etc).
Notify your Credit Card companies that you will be going away and when.
Mow the lawn before you leave (it will need it by the time you come back unless it gets cold again).
Have change on hand for the tolls if you are renting a car...or better yet, get a SunPass
Check all bags to ensure that there is nothing in them deemed "dangerous" by TSA
Thats about all I have for now...