Doesn’t God already know what our free-will choices will be...and the results of those decisions?
One theory is that omniscience is a power, not a mandate. Just because God can know, doesn't mean he can't decide not to peek at the answer. And such a decision by God (who, being all-powerful can certainly make) is critical to the idea of free-will.
Biblical accounts where God expresses disappointment seem to support this. A God who engineers or foresees an outcome cannot possibly be disappointed. And yet, there He is, angry and disappointed over and over. Or, alternatively, very happy. So He must have chosen to be surprised.
Just my two cents, anyway.