You're a courier, wounded and left for dead in a shallow grave. A friendly robot, Victor, digs you out, and his doctor owner Mitchell patches you up. You take a "vigour test", which is some sort of electric parlour game. This decides who you are and sets up SPECIAL. You can also take some Rorschach tests, but the mag says this is for fun. The Doc then gives you a Pipboy as he was once a Vault dweller.
"Hoover Dam", and "Helios" (a solar plant, confirmed by the mag to have been built by Poseidon) are fought into and then you can direct the power to wherever you choose. In the case of Helios you can also keep the plant for your self use the energy to call down a powerful laser, or even try to distribute to all equally, however there is a risk of overloading the reactors.
There is a "reputation system", in which all three factions (NCR, Ceasar's Legion and the locals) will either see you as good or bad toward them individually.
There is a screenshot of three Capital Wasteland mutants running toward the player, who is wielding what *looks* to be a heavy incinerator, but has a TV screen and no flamer fuel tanks. He's also wearing NCR combat armour, which is in gold/mustard colours.
There are two separate screens of supermutants that look to be more local, grey skin, and the two are wearing very different clothes. One is Tabitha, who is hearing a blonde wig and love heart glasses. The mag implies she's "not all there".
One that quest, you rescue Raul, a ghoul who Tabitha kept alive to fix her favourite robot. He appears to be a follower, as the mag says you can give him items, and also commands, such as "stay, follow or attack", and also tell him to switch to melee, in which case he'll mutter "sure, I'll put away my rather effective gun, and switch to this piece of um, metal tubing here".
From what I read, the "all dialog" thing seems to imply there will be failures for skill checks as well as speech checks, though, as the mag states, there is no penalty for failing a skill check. In fact, the mag gives an example: A woman who the player tried a Sneak skill attempt on in conversation failed when convincing her an ambush would help the town be rid of a gang of raiders. She simply says ""Good luck with your, uh, ambush"