It doesn't seem right to go with gold. I mean, sure, it is shiny and worth alot, but in the long run, you're going to have a hard time with the currency system. I have to say that in my opinion, it's a nice idea, but it won't work out. Caps would be cool as well, but I mean seriously, if you think about a person doing jobs for so long and never spending 1 cap, they would be running around with 50000 Bottlecaps. Where are you going to find so many caps?
You don't. A person needs to eat, drink, shoot and sleep. Unless he's a robot, he will have to buy water, food, ammo and other services, so he'll never be able to amass a load of money. Not unless he's a major entrepreneur.
Really though, although this is New Vegas, or the Post-Apocalyptic Los Vegas, having CHIPS in the game would be nice as an item, but not as the source of Currency itself. Sure, you can sell some Gaming Chips for 200 Caps. Maybe 500 Caps? But when you think of all the Raiders, don't you think they would have already stormed into all the Casinos and taken all the Chips, Money and Profitable things?
Hah, you assume Obsidian will portray Raiders as bloodthirsty savages that nail dead bodies to their walls for fun. Hint: Unlikely.
Not to mention that scavengers would choose USEFUL stuff. Poker chips are useless, in limited supply and impossible to counterfeit post-war.
So in this case, you just shouldn't bother with the Currency. Wait for awhile. Once you start seeing more about the game (Character's Backstory, New Vegas' Condition, etc.), you would have a better chance to guess what kind of Currency to use. As of right now, we don't know if New Vegas is protected by Vault Dwellers in T-51b Power Armour. For all we know, the place is held by Raiders and you need to go to a Town on the outskirts and fight your way in there.
Again, you assume Caesar's Legion is only a goon faction to shoot. It's not.
Once we all have a better idea on how the Area around New Vegas will look, we should all be able to agree on something. I think that we should wait for gamesas to release new data on the game before coming to wild conclusions like flying cars, and then get Disappointed because the things we were hoping for didn't show up in the game. A good example is one of the other Threads with the Jobs. gamesas won't put every suggestion into the game, so you should wait to see if they start taking suggestions. When/If they do, these threads will be sitting on page 731, and they won't even get looked at.
So we should just shut up and idly wait for the benevolent corporation to give us a scrap of information, instead of discussing possible ideas for the gameplay and game world?