I just did a game with the map on huge. One major thing, there are the same number of resource tiles, but now they are much more spread out. So, you will never find two luxuries within the boundaries of one city, which makes keeping the population happy much harder. In fact, unless you want your cities ridiculously strung out, which makes the costs of linking them with roads prohibitive, most of your cities will have no luxuries at all.
OTOH, you find a lot more river/floodplain tiles, simply because the river/grassy plain areas are so much larger.
The upshot of all this, is that i had a bad start to the game, forced to stop growth because of happiness issues. Tech rush buildings that give happiness, not resource harvesting techs. I'd turned off barbarians and was playing on Prince, otherwise i probably would not have made it. Finally, i got some coliseums and culture up, and started to grow fast. But up to that point i was flat out last in just about every demographic. I'd been under attack from Julius Caesar and Napoleon for a couple thousand years, since they thought me so weak.