If you don't mind a few spoilers, it's very worth the read ( and thanks to the boys and girls at NMA for posting it): http://www.pcgamer.com/2010/10/06/chugging-down-toilet-water-in-fallout-new-vegas
For existing Fallout players, it’s refreshing just to be forced into a character reboot – after 80-plus hours in Fallout 3, you could critically damage a Deathclaw with a raised eyebrow. But on top of this, the limits imposed by hardcoe mode enforce a fresh appreciation for the nutritional potential of your inventory, your health, your addictions, your tactics and your relationships with the inventories of the NPCs around you. It makes you far less blasé about the game’s systems, and makes tactical combat (and, at some points, its avoidance) a necessity rather than an occasional dalliance. The fact that your ammo now has weight means that you might become more appreciative of melee weapons, too.