Bethesda has announced they are adding a survival mode to Fallout 4 to modify the game experience raising the stakes on a multitude of levels. It is currently available in Beta on Steam but it will come to consoles sometime soon. The big changes are laid out completely on Bethesda's site but here are the highlights.
1. You can only save by sleeping, and the quality of the bed determines the quality of your recovery from sleeping in it. And fatigue is added to the game, so if you put off sleeping it starts to impact your gameplay so that you can't avoid it. I slept seldom in my first playthough and this change would have enormous consequences.
2. Fast Travel is gone. If you hear about a settlement under attack you can't teleport there to help them. Plus, you can't haul tons of stuff around and spirit it back to your base camp to stockpile. Heading to town to sell stuff, or returning home for storage are lengthy pilgrimages.
3. Damage increased - Both you and your enemies deal more damage. You need to be more careful in combat, not only because you may not have saved in awhile but because missteps can more quickly lead to your death.
4. Adrenaline was added which makes you deal more damage during battle but speeds up exhaustion. I also would guess a drug may be added to manipulate it.
5. On top of exhaustion you also have to deal with hunger and thirst. So you can't get by with just stimpaks, you need to eat and find water. I never drank radiated water in the game, but now I imagine there might be times you drink up and then take your radiation meds out of desperation.
6. Map help downgraded. The red enemy indicators only appear if you tag something with a Recon scope. So it is easier to stumble upon danger, or lose track of it.
7. You can get sick, which may speed up your thirst or exhaustion, or maybe the meds to combat it do. Certain creatures or exposure to certain items can make you ill.
8. Everything has weight including ammo. Which cuts down on hording again, and large weapon items like missiles can be quite heavy. And to make it worse the carry ability is reduced, you hurt yourself exceeding that weight and can even cripple your legs. Which leads to the next item.
9. Crippled limbs don't auto heal after combat and will require stimpaks or a bed to resolve.
10. Your companions are not as helpful (can't carry as much) and they don't get back up after combat unless you heal them. If you forget to heal them they will wander home abandoned.
All of these changes are brutal, and I love them. I kinda wish I had been playing under these conditions from the get go. I bet this mode makes the guides more valuable.