Some thoughts...
I'm a contractor at NYSEG in Binghamton. Last year they went through the floods after Hurricane Irene, and this year they faced major power outages in their downstate territories with Sandy. Power outages are a fact of life in a natural disaster type of scenario. Everyone wants to condemn the power company for not getting the power on fast enough - but it's a slow, orderly and methodical process that can take some time. Safety trumps all as it's an industry where mistakes cost lives. So be prepared to wait...
Lots of the crying coming from the hurricane victims in the NYC area were really a result of simply not being prepared for an extended power outage. It's not rocket science.
Water - if you're on a public water supply, you're fine. My brother-in-law works for OCWA in Syracuse and he helps maintains the distribution system. He said everything's on generator backup, and there's redundant sources of water (i.e., Lake Ontario and Skaneateles Lake). It would take a major catastrophe to take out the water supply. If you're on well water - then you should be keeping a rotating stock of fresh water in 1 or 5 gallon containers. Figure a half gallon per day per person in your household to survive so long as they're not running marathons in 95 degree heat. Family of 4 will need 14 gallons for a week. We're on a public supply. Worse comes to worse, I grab a 5-gallon bucket, run up to the lake, and use a Brita filter for drinking water.
Food - my wife does the coupon clipping thing and stocks up on non-perishables that we keep in a basement pantry when stuff is on sale - not for survival purposes but she just buys stuff in bulk. So win-win. The food gets rotated out as it's used before it expires or before it gets to be 6 months old - whatever is shorter. We have a good week+ of food to eat. Get one of those freezer chests to keep in the basement, keep several bags of ice in there and store your perishables. You'll get several days of cold food so long as you're not going in there every 15 minutes. Eat that stuff first while it's still fresh then work on the non-perishable supply.
Electricity - figure out how much you realistically "need" and have an alternate source of power to run those items for a week or two. Doesn't have to be a generator - grab a 1000 watt power inverter from Harbor Freight for $80 (or use the 20% off coupon from their American Rifleman ad). Most car engines burn around a 1/2 gallon per hour while idling with things like the AC turned off. A full tank of gas can run the necessities for more than a week if you ration carefully. Don't need to run lights during the day (duh), and things like cell phones can be charged off of a simple lead-gel battery (the types you find in alarm systems, computer UPS's, etc...) by wiring a cigarette lighter plug to the battery terminals - and you'll easily get a good week or two of use between charges. I have a couple of neighbors with standby generators that run on natural gas and kick on automatically when the power goes out. Needless-to-say, in an extended power outage situation, they'll become everyone's best friend. I just have a couple of inverters to run off the cars which will meet our needs (a few CFL lamps, LED back-lit flat-screen TV, personal electronics, the fridge if needed, etc...).
Fuel - like food, water, and other things - gasoline has a limited shelf life... so have a stock of fuel to rotate to run things like generators, your car, etc... keep 3-4 five gallon cans and use them to keep your lawn toys fueled up. Adding StaBil will increase the life of the fuel. If possible, use gas that doesn't have ethanol added to it. If you have a gas BBQ grill, keep an extra tank of propane handy. For me - work truck has 35 gallon tank, the wife's car holds 18 gallons. I got two 5-gallon gas cans for power equipment, and three 6-gallon tanks on the boat. Storm's a comin' - fill 'em up and I got a good week or two of fuel without waiting on line for 4 hours after the fact. What I don't use during an emergency will be used up within two weeks just from driving to work, etc.
Heat - if you have a wood stove or fireplace, you're golden so long as the flue works properly and you have an ample supply of wood (or coal, or wood pellets if you have those - pellet stoves can run off a marine battery as a backup too). If your hot water heater is fired by natural gas or propane, you'll have a supply of hot water so long as your water supply works. Fill up the tub with hot water - it'll provide a source of heat for a while. We have a fireplace and usually keep a face-cord of firewood in the garage.
Money - keep a week or two of the cash you'll need in a easily accessible but safe place (ATM's and credit card machines need power). Don't worry about your bills... get them to waive late fees when you get back.
Job/Employment - got sick days? Vacation time? Banked PTO? Take some off and don't worry about consuming gasoline to commute. My job is field based - so working out of home and going where I have to go isn't a problem. The wife works for the state and has 8 months of sick/vacation time banked up. You don't always have to stay local and fight for food/gas with the rest of your neighbors if you are able to take time off from work and stay at a hotel or with family a few hours away.
Weapons / ammo - let's not get too carried away... bring your carry piece and a couple of mags worth of ammo. You're not going to be fighting it out in the streets as though you're in downtown Fallujah like it's 2003.
Bugging out - realistically, most of us have family and friends within an easy drive out of the disaster area. You don't have to stay in a cold / dark house waiting for the electric company to turn the power back on. Secure your valuables, turn off the main circuit breakers, turn off the gas to the stove/hot water heater/furnace, etc... and lock up. If it's winter - let water dribble from the sinks (both hot and cold) so the water lines don't freeze. When I saw Hurricane Sandy coming up the coast, I booked a room in Binghamton for a week knowing I'd be staying there for about that long for work (turned out to be 2 weeks). Most reservations are refundable... if it turns out you don't need it - just cancel the reservation, but the point being is - secure a second place to stay before the storm, rather than after the storm along with everyone else who thought of that great idea afterwards. Cursory glances at Hotels.com showed there were tons of vacancies just several hours from the NYC/LI/NJ area in the Binghamton area during aftermath. Most hotels provide free breakfast, coffee, toiletries, plenty of fresh water, hot showers, HVAC, etc... etc. We have also friends/family within a 2 hour drive and further out if needed.
So there you have it. No fancy underground bunker with 6 months of provisions needed. History so far has shown that at worst, you'll be inconvenienced for a week or two so long as you don't lose your home to a flood, fire, tornado, etc. Common sense dictates that a week without power is easily survivable. It won't be fun - but it's certainly doable.
Granted, I live in a house, have a good income and good resources - not in a high-rise Section 8 apartment building where they don't have the amenities like we do - and even still, with some planning, those folks can ride out a power outage for a while. BUT... I also made a choice of where we live based on the ability to withstand what nature throws our way. When house hunting, I made sure we had public water, consulted FEMA flood maps and topographic maps to make sure we wouldn't be needing the boat to get out of our neighborhood. Again - common sense.
