Only worthwhile if you have online friends who have this game. Otherwise it's only as fun as picking up rocks outside.
Anytime I play Catan, the board game, with my friends and manage to hold onto my ore and wheat long enough to build a thriving metropolis out of one of my rural settlements, I can't help but sing that. Anytime I try to play the electronic version of Catan, I can't help but throw my controller at ninety miles an hour at my dog. Even if you're familiar with the rules of the game, this bland, unforgiving rendition of it will make you feel like an outsider who only received an invite to the game because you make the best spinach dip.
The tutorial helps to explain the rules, but there is nothing in this game to help you develop any kind of strategy against the AI even on easy difficulty. Computer opponents will constantly trade with each other, but they tend to never accept your proposed trades, so any time you accept one of their swaps all you're doing is helping them beat you all the faster. So trading, which is a viable option with human opponents, is completly moot as a strategy when dealing with the game's AI. It doesn't help that the trading screen is too busy, and one of your opponents beats you to the deal before you have the chance to figure out who needs what and what they're willing to part with for it.
The game might be easier for a beginner to warm up to if you could limit the number of players to 3 or 2 (even though the board game sets a minimum of 3, a 2-player game is not only possible, but fun). But no, you're stuck with four. And I don't appreciate the fact that each loss is recorded among my stats for all time when I'm just trying to play some exhibition matches to learn the nuances of the game.
Also, don't expect to be able to play "Seafarers," "Cities and Knights," "Traders and Barbarians" or any of the other add-ons available for the board game. It's just the original Settlers of Catan, which would be fine if the developers had spent more time on making the AI more forgiving to new players. Even though you can vary the visual options, there just isn't enough variety to keep the game from going stale before you even become very good at it.