While it does get (a tad) repetetive, it's only the first half hour (depending on how you play) that has that is repetetive. Get past that stage and you've got (almost) unlimited replay value.
you could easily sink more than 10 hours into a single game, or in a single sitting.
Both a game for the casual and the semi-hardcore, depending on how you roll. You can get both a peaceful map, where you focus on building. Or a map with a number of enemies that you have to destroy.
The graphics are great, lifelike and you can easily tell what's a tree and what's not a tree, and so on.