So far I'm pretty pleased with the game. Everything I liked about Fallout 3 is present and there are several tweaks I really dig.
- Hardcore mode. This mode not only more difficult but you have to monitor your sleep level, food level, and hydration - the same as you have to monitor your rads. Ammunition now has weight so you can't run around with ten thousand rounds of every kind of ammo.
- Crafting is actually worth a shit now. You can break down unused ammo into supplies and then use those supplies to craft better ammo (armor piercing, etc, etc). You can combine ingredients at campfires for impromtu food, healing items. It certainly makes for a more tailored style of game play. I'm doing exceptionally well with a silenced .22 with HP rounds (one shot one kill if in stealth).
- A trick for hardcore mode - while ammo has weight, the components do not. What I did was break down all the ammunition I didn't have weapons for into components. Plus I was able to craft some better ammo for the weapons I do use. Better ammo is also better for maintaining your weapons.
- I haven't gotten that far into the perks and upgrades so there will more info to come as I unlock those.
- Iron sights! Since my V.A.T.S is still low level I've been using the iron sights a lot. This is great, since I got tired of using V.A.T.S as a crutch in Fallout 3. Plus it helps for one shot, one kill, sneaky tactics.