It's a fairly light board game that plays quickly and can be played with anywhere from 2 to 7 players (though the 2 player variant uses a dummy player so ehh) and it takes the same amount of time for any number of players so it's nice in that respect.
Basically it's a card drafting game. Each player is given a hand of 7 cards, they pick one to play, and pass the rest. The cards represent buildings you're adding to your city, and there are several different types which gives you plenty of ways to play. Each player also is building a different wonder throughout the game (e.g. Hanging Gardens, Pyramids, etc) and each wonder has a different special features which will steer you in a different direction.
It's an easy to pick up game and it plays very quickly (about 30 minutes once everyone knows the rules), while having enough depth to be interesting upon multiple replays. I've played 5 games and ended up approaching them all completely different and I've seen every strategy be at least somewhat viable -- whether that's spreading yourself out among the different aspects (financial / scientific / military / arts / resources) or focusing on one almost exclusively. It's a neat game.
My only real complaints is that the game is really heavy on symbols. The only words on any part of the game are the names of the card which don't explain what they do. It makes it so there's no language requirement, but it makes it so it's a bit intimidating for a new player.. There's a handy reference sheet for symbols, so I guess it isn't too bad. My other complaint is that with more players the amount of interaction seems to drop a lot. You can only directly interact with your two neighbors, and as the game gets larger there are more players you can't really touch at all. The game feels a lot different with 3 and 5+ players.
There are lots of expansions planned it seems -- similar to Dominion. I haven't gotten any of them, but I fear they'd bloat the game and make it take longer. If I'm going to be playing an hour+ game I'd probably pick something with a bit more meat to it.
... oh god I wrote more than you wanted probably. Long story short: great game for a wide range of players that plays quickly. Everyone I've played it with has liked it so far -- more than other games like Settlers or Power Grid which can drag on a bit.
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No amount of planning will ever replace dumb luck.