i've played it several times, but i've never been that impressed with it.
the game starts by shuffling hex-shaped terrain cards, and placing them on the table, surrounded by water hexes. this is Catan, i would surmise. then there are cardboard circles with numbers on them corresponding to the numbers you get when rolling 2d6, except 7. roll to see who places a town first. whoever does picks the prime location for his town, and places one road next to it. each person in succession places one town and one road, then when it gets to the last person, then it goes backwards back up to the first person, like 1 2 3 4 5 6 6 5 4 3 2 1. it's good to be 1, 2, and 6, because those people tend to get the best resources. towns are placed at the intersections of hexes.
play goes like this: the player rolls 2d6, say they roll 9. everybody with a town adjacent to a terrain that has a cardboard circle on it with the number 9 gets one of whatever resource that terrain makes. the resources let you build things like roads and towns, and upgrade towns to cities, and buy special cards that have various effects.
... i realize i'm going into way too much detail here.
anyway. the goal is to get 10 points. you get 1 point for every town you have, 2 for every city you have, 2 points if you have the longest road, 2 points if you have the highest number of a certain kind of card. however, once everybody has placed roads, the board becomes pretty static and it's just a matter of how well you placed your towns. like if you screwed up and failed to put a town near any mountains, you won't get any Ore unless you trade for it, which puts you at an insurmountable disadvantage.
my biggest nit to pick with the game is that there's no conquest of any kind. you're supposed to be enemies with your neighbors but it's like everybody is switzerland. there's no way to remove somebody's road if it's in your way, and there's no way to smack somebody down if they're about to win. the only thing you can do during the mid- and late-game is levy economic sanctions, which only delays the win for a few turns.
it's too much based on luck (good die rolls = good economy and you win, bad die rolls = bad economy and you lose)
don't lay down hard-earned cash on buying it, but if somebody you know has it, find some ppl and play a couple rounds, to get the sense of novelty out.