So, at the last minute, I got a copy of 7 Wonders for my family for Christmas since I figured having more board games around couldn't hurt. My decision process was roughly to scan the highest-rated games on BoardGameGeek that were good for 5 or so people and weren't too complicated, and it seems to have paid off.
The core idea of the game is that, over three ages, you want to build the best city you can along some (combination of) metric(s) to win, that is, you want the most victory points. At the beginning each age, you get 7 cards (with the sets of cards being different in each age) and, on each turn, you choose a card to play (or sell, or to use to keep building the unique ancient wonder in your city) and then you pass your hands around the table. This also means that everyone's playing simultaneously, so there's not really any sitting around and waiting, and, since, there's a fixed number of turns, so each game takes a rather quick half an hour.
The rules are rather straightforward but are somewhat tricky to explain, so your first round will probably include some confusion (unless you're the sort of group that passes around the (rather short) manual beforehard) but it's not all that complex a game to get the hang of, and you'll soon find yourself understanding enough to form a plan - and to start eyeing your neighbors for how you can take advantage of their plans (since there are cards that'll give you points based on how your neighbors at the table are doing) ... or mess them up (by not giving them cards they need).
The game does need a reasonably-sized group of people (4 to 6 or so - the minimum is 3 but that might be a somewhat different experience, and the maximum is 7), but I can report having a good time - and, as our second game was wrapping up, we were thoroughly enjoying ourselves and my mom was saying we should get this for our aunt.
Anyway, this has been a rambly review-shaped object in case anyone wants it.